Vulnerability-Lookup

CVE-2026-74621 (GCVE-0-2026-74621)

Vulnerability from cvelistv5 – Published: 2026-08-22 15:32 – Updated: 2026-08-25 05:40

Title

net/sched: act_ct: fix sk_buff leak when the header checks reject a packet

Summary

In the Linux kernel, the following vulnerability has been resolved: net/sched: act_ct: fix sk_buff leak when the header checks reject a packet tcf_ct_handle_fragments() runs its header sanity checks before handing anything to the defragmentation engine: if (family == NFPROTO_IPV4) err = tcf_ct_ipv4_is_fragment(skb, &frag); else err = tcf_ct_ipv6_is_fragment(skb, &frag); if (err || !frag) return err; tcf_ct_ipv4_is_fragment() returns -EINVAL or -ENOMEM; tcf_ct_ipv6_is_fragment() adds -EPROTO when ipv6_find_hdr() fails. None of them frees or queues the skb, so on that path the caller still owns it. tcf_ct_act() however funnels every non-zero return into the ownership-transfer exit: err = tcf_ct_handle_fragments(net, skb, family, p->zone, &defrag); if (err) goto out_frag; ... out_frag: if (err != -EINPROGRESS) tcf_action_inc_drop_qstats(&c->common); return TC_ACT_CONSUMED; TC_ACT_CONSUMED means the action took ownership of the skb, so no caller frees it - sch_handle_ingress(), sch_handle_egress() and tcf_qevent_handle() all deliberately skip the free for that verdict. The skb is therefore orphaned: one sk_buff plus its data buffer is leaked per malformed packet, unbounded. Note the drop counter is already incremented for these errors, so the statistics claim a drop that never happens. Three different ownership states reach out_frag: today - the skb may be queued by the defrag engine (-EINPROGRESS), already freed by nf_ct_handle_fragments(), or still owned by us. Tell the caller which of those it is, and free the packet ourselves in the last case, which restores the TC_ACT_SHOT behaviour that predated the Fixes: commit. Reproduced on v7.2-rc6 with a 54-byte frame carrying a 40-byte IPv6 header with nexthdr = 0 (hop-by-hop) and nothing after it, on a clsact ingress chain with "action ct". kmemleak reports one leaked 232-byte skbuff_head_cache object plus its 704-byte data buffer per packet; with this patch it reports none.

Severity

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Assigner

Linux mitre root

References

7 references

URL	Tags
https://git.kernel.org/stable/c/b5dbecc2016e1692f…
https://git.kernel.org/stable/c/23e97d594ddd01530…
https://git.kernel.org/stable/c/737873a59905a54ca…
https://git.kernel.org/stable/c/47d99828591d0fe8b…
https://git.kernel.org/stable/c/b47bb899e04b5407c…
https://git.kernel.org/stable/c/439d3e404f9d5e515…
https://git.kernel.org/stable/c/8a7ed561671aa6a91…

Impacted products

2 products

Vendor	Product	Version	CPE status
Linux	Linux	Affected: 172ba7d46c202e679f3ccb10264c67416aaeb1c4 , < b5dbecc2016e1692fd1c2532af9c41ba729cb747 (git) Affected: 0b5b831122fc3789fff75be433ba3e4dd7b779d4 , < 23e97d594ddd0153020c506d5041048fbde1beb4 (git) Affected: 73f7da5fd124f2cda9161e2e46114915e6e82e97 , < 737873a59905a54ca0d2d127ef882f3f88bf4379 (git) Affected: 3f14b377d01d8357eba032b4cabc8c1149b458b6 , < 47d99828591d0fe8be4b9c8992ff3b8e47968db9 (git) Affected: 3f14b377d01d8357eba032b4cabc8c1149b458b6 , < b47bb899e04b5407c5a63fe88d4b6676586a6e84 (git) Affected: 3f14b377d01d8357eba032b4cabc8c1149b458b6 , < 439d3e404f9d5e515911cc8132cde198b337c19e (git) Affected: 3f14b377d01d8357eba032b4cabc8c1149b458b6 , < 8a7ed561671aa6a911a2de99e59ef670a4d0b1df (git) Affected: f5346df0591d10bc948761ca854b1fae6d2ef441 (git) Affected: 5.15.148 , < 5.15.217 (semver) Affected: 6.1.75 , < 6.1.184 (semver) Affected: 6.6.14 , < 6.6.152 (semver) Affected: 6.7.2 , < 6.8 (semver)	guessed
Linux	Linux	Affected: 6.8 Unaffected: 0 , < 6.8 (semver) Unaffected: 5.15.217 , ≤ 5.15.* (semver) Unaffected: 6.1.184 , ≤ 6.1.* (semver) Unaffected: 6.6.152 , ≤ 6.6.* (semver) Unaffected: 6.12.104 , ≤ 6.12.* (semver) Unaffected: 6.18.45 , ≤ 6.18.* (semver) Unaffected: 7.1.9 , ≤ 7.1.* (semver) Unaffected: 7.2 , ≤ * (original_commit_for_fix)	guessed

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{
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          "programFiles": [
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          "product": "Linux",
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          ],
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          "vendor": "Linux",
          "versions": [
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              "status": "unaffected",
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              "versionType": "semver"
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              "status": "unaffected",
              "version": "5.15.217",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.184",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.152",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.104",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.45",
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            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.9",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
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                  "vulnerable": true
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                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.184",
                  "versionStartIncluding": "6.1.75",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.152",
                  "versionStartIncluding": "6.6.14",
                  "vulnerable": true
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                {
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                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                  "versionStartIncluding": "6.8",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: act_ct: fix sk_buff leak when the header checks reject a packet\n\ntcf_ct_handle_fragments() runs its header sanity checks before handing\nanything to the defragmentation engine:\n\n\tif (family == NFPROTO_IPV4)\n\t\terr = tcf_ct_ipv4_is_fragment(skb, \u0026frag);\n\telse\n\t\terr = tcf_ct_ipv6_is_fragment(skb, \u0026frag);\n\tif (err || !frag)\n\t\treturn err;\n\ntcf_ct_ipv4_is_fragment() returns -EINVAL or -ENOMEM;\ntcf_ct_ipv6_is_fragment() adds -EPROTO when ipv6_find_hdr() fails. None of\nthem frees or queues the skb, so on that path the caller still owns it.\n\ntcf_ct_act() however funnels every non-zero return into the\nownership-transfer exit:\n\n\terr = tcf_ct_handle_fragments(net, skb, family, p-\u003ezone, \u0026defrag);\n\tif (err)\n\t\tgoto out_frag;\n\t...\nout_frag:\n\tif (err != -EINPROGRESS)\n\t\ttcf_action_inc_drop_qstats(\u0026c-\u003ecommon);\n\treturn TC_ACT_CONSUMED;\n\nTC_ACT_CONSUMED means the action took ownership of the skb, so no caller\nfrees it - sch_handle_ingress(), sch_handle_egress() and\ntcf_qevent_handle() all deliberately skip the free for that verdict. The\nskb is therefore orphaned: one sk_buff plus its data buffer is leaked per\nmalformed packet, unbounded. Note the drop counter is already incremented\nfor these errors, so the statistics claim a drop that never happens.\n\nThree different ownership states reach out_frag: today - the skb may be\nqueued by the defrag engine (-EINPROGRESS), already freed by\nnf_ct_handle_fragments(), or still owned by us. Tell the caller which of\nthose it is, and free the packet ourselves in the last case, which\nrestores the TC_ACT_SHOT behaviour that predated the Fixes: commit.\n\nReproduced on v7.2-rc6 with a 54-byte frame carrying a 40-byte IPv6\nheader with nexthdr = 0 (hop-by-hop) and nothing after it, on a\nclsact ingress chain with \"action ct\". kmemleak reports one leaked\n232-byte skbuff_head_cache object plus its 704-byte data buffer per\npacket; with this patch it reports none."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - The leak is triggered in tcf_ct_act() on the packet datapath (netif_receive_skb \u2192 sch_handle_ingress/egress \u2192 tc_run \u2192 tcf_classify); on OVN/Kubernetes/SDN gateways and mlx5-offload nodes with act_ct on clsact, a remote peer sends malformed IP packets with no local access required.\nAC:L - The attacker fully controls packet contents; a 54-byte IPv6 frame with nexthdr=0 (hop-by-hop) and no trailing data deterministically makes ipv6_find_hdr() return -EPROTO, leaking one skb per packet without races or uncontrollable layout dependencies.\nPR:N - Installing act_ct requires CAP_NET_ADMIN, but triggering the leak on an already-configured internet-facing or tenant-facing gateway needs no target credentials; a remote attacker only sends crafted malformed IP packets, matching CNA precedent for packet-driven act_ct issues (e.g., CVE-2026-72057).\nUI:N - Exploitation requires only attacker-generated malformed packets reaching a host with act_ct on clsact/ingress or egress; no victim login, mount, or other interactive action is needed beyond normal network traffic processing.\nS:U - The leaked sk_buff objects remain within the host kernel memory domain; this is not a VM escape, sandbox breakout, or IOMMU boundary bypass, only unbounded kernel heap consumption on the affected node.\nC:N - This is a pure sk_buff ownership leak on an error path; skb memory is orphaned, not exposed to the attacker, with no out-of-bounds read, use-after-free, or other disclosure primitive.\nI:N - The flaw only fails to kfree_skb() when header validation rejects a packet; it does not corrupt, overwrite, or modify any memory contents and provides no write or code-execution primitive.\nA:H - Each malformed packet leaks one sk_buff plus its data buffer (~936 bytes); sustained remote flooding causes unbounded kernel memory exhaustion and OOM denial of service, matching CNA precedent for repeatable network-triggered skb leaks (e.g., CVE-2026-52974)."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-25T05:40:45.894Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/b5dbecc2016e1692fd1c2532af9c41ba729cb747"
        },
        {
          "url": "https://git.kernel.org/stable/c/23e97d594ddd0153020c506d5041048fbde1beb4"
        },
        {
          "url": "https://git.kernel.org/stable/c/737873a59905a54ca0d2d127ef882f3f88bf4379"
        },
        {
          "url": "https://git.kernel.org/stable/c/47d99828591d0fe8be4b9c8992ff3b8e47968db9"
        },
        {
          "url": "https://git.kernel.org/stable/c/b47bb899e04b5407c5a63fe88d4b6676586a6e84"
        },
        {
          "url": "https://git.kernel.org/stable/c/439d3e404f9d5e515911cc8132cde198b337c19e"
        },
        {
          "url": "https://git.kernel.org/stable/c/8a7ed561671aa6a911a2de99e59ef670a4d0b1df"
        }
      ],
      "title": "net/sched: act_ct: fix sk_buff leak when the header checks reject a packet",
      "x_generator": {
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    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-74621",
    "datePublished": "2026-08-22T15:32:04.990Z",
    "dateReserved": "2026-08-15T05:44:03.921Z",
    "dateUpdated": "2026-08-25T05:40:45.894Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-74621",
      "date": "2026-08-27",
      "epss": "0.0049",
      "percentile": "0.40065"
    },
    "microsoft_vex": {
      "current_release_date": "2026-08-24T14:46:12.000Z",
      "cve": "CVE-2026-74621",
      "id": "msrc_CVE-2026-74621",
      "initial_release_date": "2026-08-24T01:02:45.000Z",
      "product_status:known_affected": "1",
      "source": "Microsoft CSAF VEX",
      "status": "final",
      "title": "net/sched: act_ct: fix sk_buff leak when the header checks reject a packet",
      "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-74621.json",
      "version": "2"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-74621\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-08-22T16:16:34.897\",\"lastModified\":\"2026-08-25T06:18:40.510\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nnet/sched: act_ct: fix sk_buff leak when the header checks reject a packet\\n\\ntcf_ct_handle_fragments() runs its header sanity checks before handing\\nanything to the defragmentation engine:\\n\\n\\tif (family == NFPROTO_IPV4)\\n\\t\\terr = tcf_ct_ipv4_is_fragment(skb, \u0026frag);\\n\\telse\\n\\t\\terr = tcf_ct_ipv6_is_fragment(skb, \u0026frag);\\n\\tif (err || !frag)\\n\\t\\treturn err;\\n\\ntcf_ct_ipv4_is_fragment() returns -EINVAL or -ENOMEM;\\ntcf_ct_ipv6_is_fragment() adds -EPROTO when ipv6_find_hdr() fails. None of\\nthem frees or queues the skb, so on that path the caller still owns it.\\n\\ntcf_ct_act() however funnels every non-zero return into the\\nownership-transfer exit:\\n\\n\\terr = tcf_ct_handle_fragments(net, skb, family, p-\u003ezone, \u0026defrag);\\n\\tif (err)\\n\\t\\tgoto out_frag;\\n\\t...\\nout_frag:\\n\\tif (err != -EINPROGRESS)\\n\\t\\ttcf_action_inc_drop_qstats(\u0026c-\u003ecommon);\\n\\treturn TC_ACT_CONSUMED;\\n\\nTC_ACT_CONSUMED means the action took ownership of the skb, so no caller\\nfrees it - sch_handle_ingress(), sch_handle_egress() and\\ntcf_qevent_handle() all deliberately skip the free for that verdict. The\\nskb is therefore orphaned: one sk_buff plus its data buffer is leaked per\\nmalformed packet, unbounded. Note the drop counter is already incremented\\nfor these errors, so the statistics claim a drop that never happens.\\n\\nThree different ownership states reach out_frag: today - the skb may be\\nqueued by the defrag engine (-EINPROGRESS), already freed by\\nnf_ct_handle_fragments(), or still owned by us. Tell the caller which of\\nthose it is, and free the packet ourselves in the last case, which\\nrestores the TC_ACT_SHOT behaviour that predated the Fixes: commit.\\n\\nReproduced on v7.2-rc6 with a 54-byte frame carrying a 40-byte IPv6\\nheader with nexthdr = 0 (hop-by-hop) and nothing after it, on a\\nclsact ingress chain with \\\"action ct\\\". kmemleak reports one leaked\\n232-byte skbuff_head_cache object plus its 704-byte data buffer per\\npacket; with this patch it reports none.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"net/sched/act_ct.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"172ba7d46c202e679f3ccb10264c67416aaeb1c4\",\"lessThan\":\"b5dbecc2016e1692fd1c2532af9c41ba729cb747\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"0b5b831122fc3789fff75be433ba3e4dd7b779d4\",\"lessThan\":\"23e97d594ddd0153020c506d5041048fbde1beb4\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"73f7da5fd124f2cda9161e2e46114915e6e82e97\",\"lessThan\":\"737873a59905a54ca0d2d127ef882f3f88bf4379\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3f14b377d01d8357eba032b4cabc8c1149b458b6\",\"lessThan\":\"47d99828591d0fe8be4b9c8992ff3b8e47968db9\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3f14b377d01d8357eba032b4cabc8c1149b458b6\",\"lessThan\":\"b47bb899e04b5407c5a63fe88d4b6676586a6e84\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3f14b377d01d8357eba032b4cabc8c1149b458b6\",\"lessThan\":\"439d3e404f9d5e515911cc8132cde198b337c19e\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3f14b377d01d8357eba032b4cabc8c1149b458b6\",\"lessThan\":\"8a7ed561671aa6a911a2de99e59ef670a4d0b1df\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"f5346df0591d10bc948761ca854b1fae6d2ef441\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"5.15.148\",\"lessThan\":\"5.15.217\",\"versionType\":\"semver\",\"status\":\"affected\"},{\"version\":\"6.1.75\",\"lessThan\":\"6.1.184\",\"versionType\":\"semver\",\"status\":\"affected\"},{\"version\":\"6.6.14\",\"lessThan\":\"6.6.152\",\"versionType\":\"semver\",\"status\":\"affected\"},{\"version\":\"6.7.2\",\"lessThan\":\"6.8\",\"versionType\":\"semver\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"net/sched/act_ct.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"6.8\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"6.8\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.15.217\",\"lessThanOrEqual\":\"5.15.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.184\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.152\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.104\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.45\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.1.9\",\"lessThanOrEqual\":\"7.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.2\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H\",\"baseScore\":7.5,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":3.9,\"impactScore\":3.6}]},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/23e97d594ddd0153020c506d5041048fbde1beb4\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/439d3e404f9d5e515911cc8132cde198b337c19e\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/47d99828591d0fe8be4b9c8992ff3b8e47968db9\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/737873a59905a54ca0d2d127ef882f3f88bf4379\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/8a7ed561671aa6a911a2de99e59ef670a4d0b1df\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/b47bb899e04b5407c5a63fe88d4b6676586a6e84\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/b5dbecc2016e1692fd1c2532af9c41ba729cb747\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-08-25T08:51:15+00:00",
      "cve": "CVE-2026-74621",
      "id": "CVE-2026-74621",
      "initial_release_date": "2026-08-22T00:00:00+00:00",
      "product_status:known_affected": "232",
      "product_status:known_not_affected": "42",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: net/sched: act_ct: fix sk_buff leak when the header checks reject a packet",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-74621.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "not set",
      "current_release_date": "2026-08-23T00:05:47Z",
      "cve": "CVE-2026-74621",
      "id": "CVE-2026-74621",
      "initial_release_date": "2026-08-23T00:05:47Z",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-74621",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-74621.json",
      "version": "2"
    }
  }
}

FKIE_CVE-2026-74621

Vulnerability from fkie_nvd - Published: 2026-08-22 16:16 - Updated: 2026-08-25 06:18

Severity

7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Summary

References

	URL	Tags
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/23e97d594ddd0153020c506d5041048fbde1beb4
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/439d3e404f9d5e515911cc8132cde198b337c19e
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/47d99828591d0fe8be4b9c8992ff3b8e47968db9
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/737873a59905a54ca0d2d127ef882f3f88bf4379
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/8a7ed561671aa6a911a2de99e59ef670a4d0b1df
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/b47bb899e04b5407c5a63fe88d4b6676586a6e84
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/b5dbecc2016e1692fd1c2532af9c41ba729cb747

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/sched/act_ct.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "b5dbecc2016e1692fd1c2532af9c41ba729cb747",
              "status": "affected",
              "version": "172ba7d46c202e679f3ccb10264c67416aaeb1c4",
              "versionType": "git"
            },
            {
              "lessThan": "23e97d594ddd0153020c506d5041048fbde1beb4",
              "status": "affected",
              "version": "0b5b831122fc3789fff75be433ba3e4dd7b779d4",
              "versionType": "git"
            },
            {
              "lessThan": "737873a59905a54ca0d2d127ef882f3f88bf4379",
              "status": "affected",
              "version": "73f7da5fd124f2cda9161e2e46114915e6e82e97",
              "versionType": "git"
            },
            {
              "lessThan": "47d99828591d0fe8be4b9c8992ff3b8e47968db9",
              "status": "affected",
              "version": "3f14b377d01d8357eba032b4cabc8c1149b458b6",
              "versionType": "git"
            },
            {
              "lessThan": "b47bb899e04b5407c5a63fe88d4b6676586a6e84",
              "status": "affected",
              "version": "3f14b377d01d8357eba032b4cabc8c1149b458b6",
              "versionType": "git"
            },
            {
              "lessThan": "439d3e404f9d5e515911cc8132cde198b337c19e",
              "status": "affected",
              "version": "3f14b377d01d8357eba032b4cabc8c1149b458b6",
              "versionType": "git"
            },
            {
              "lessThan": "8a7ed561671aa6a911a2de99e59ef670a4d0b1df",
              "status": "affected",
              "version": "3f14b377d01d8357eba032b4cabc8c1149b458b6",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "f5346df0591d10bc948761ca854b1fae6d2ef441",
              "versionType": "git"
            },
            {
              "lessThan": "5.15.217",
              "status": "affected",
              "version": "5.15.148",
              "versionType": "semver"
            },
            {
              "lessThan": "6.1.184",
              "status": "affected",
              "version": "6.1.75",
              "versionType": "semver"
            },
            {
              "lessThan": "6.6.152",
              "status": "affected",
              "version": "6.6.14",
              "versionType": "semver"
            },
            {
              "lessThan": "6.8",
              "status": "affected",
              "version": "6.7.2",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/sched/act_ct.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.8"
            },
            {
              "lessThan": "6.8",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.217",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.184",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.152",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.104",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.45",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.9",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: act_ct: fix sk_buff leak when the header checks reject a packet\n\ntcf_ct_handle_fragments() runs its header sanity checks before handing\nanything to the defragmentation engine:\n\n\tif (family == NFPROTO_IPV4)\n\t\terr = tcf_ct_ipv4_is_fragment(skb, \u0026frag);\n\telse\n\t\terr = tcf_ct_ipv6_is_fragment(skb, \u0026frag);\n\tif (err || !frag)\n\t\treturn err;\n\ntcf_ct_ipv4_is_fragment() returns -EINVAL or -ENOMEM;\ntcf_ct_ipv6_is_fragment() adds -EPROTO when ipv6_find_hdr() fails. None of\nthem frees or queues the skb, so on that path the caller still owns it.\n\ntcf_ct_act() however funnels every non-zero return into the\nownership-transfer exit:\n\n\terr = tcf_ct_handle_fragments(net, skb, family, p-\u003ezone, \u0026defrag);\n\tif (err)\n\t\tgoto out_frag;\n\t...\nout_frag:\n\tif (err != -EINPROGRESS)\n\t\ttcf_action_inc_drop_qstats(\u0026c-\u003ecommon);\n\treturn TC_ACT_CONSUMED;\n\nTC_ACT_CONSUMED means the action took ownership of the skb, so no caller\nfrees it - sch_handle_ingress(), sch_handle_egress() and\ntcf_qevent_handle() all deliberately skip the free for that verdict. The\nskb is therefore orphaned: one sk_buff plus its data buffer is leaked per\nmalformed packet, unbounded. Note the drop counter is already incremented\nfor these errors, so the statistics claim a drop that never happens.\n\nThree different ownership states reach out_frag: today - the skb may be\nqueued by the defrag engine (-EINPROGRESS), already freed by\nnf_ct_handle_fragments(), or still owned by us. Tell the caller which of\nthose it is, and free the packet ourselves in the last case, which\nrestores the TC_ACT_SHOT behaviour that predated the Fixes: commit.\n\nReproduced on v7.2-rc6 with a 54-byte frame carrying a 40-byte IPv6\nheader with nexthdr = 0 (hop-by-hop) and nothing after it, on a\nclsact ingress chain with \"action ct\". kmemleak reports one leaked\n232-byte skbuff_head_cache object plus its 704-byte data buffer per\npacket; with this patch it reports none."
    }
  ],
  "id": "CVE-2026-74621",
  "lastModified": "2026-08-25T06:18:40.510",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6,
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-08-22T16:16:34.897",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/23e97d594ddd0153020c506d5041048fbde1beb4"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/439d3e404f9d5e515911cc8132cde198b337c19e"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/47d99828591d0fe8be4b9c8992ff3b8e47968db9"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/737873a59905a54ca0d2d127ef882f3f88bf4379"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/8a7ed561671aa6a911a2de99e59ef670a4d0b1df"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/b47bb899e04b5407c5a63fe88d4b6676586a6e84"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/b5dbecc2016e1692fd1c2532af9c41ba729cb747"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}

GHSA-PJMQ-J37R-3MM4

Vulnerability from github – Published: 2026-08-22 18:30 – Updated: 2026-08-25 06:31

Details

In the Linux kernel, the following vulnerability has been resolved:

net/sched: act_ct: fix sk_buff leak when the header checks reject a packet

tcf_ct_handle_fragments() runs its header sanity checks before handing anything to the defragmentation engine:

if (family == NFPROTO_IPV4)
    err = tcf_ct_ipv4_is_fragment(skb, &frag);
else
    err = tcf_ct_ipv6_is_fragment(skb, &frag);
if (err || !frag)
    return err;

tcf_ct_ipv4_is_fragment() returns -EINVAL or -ENOMEM; tcf_ct_ipv6_is_fragment() adds -EPROTO when ipv6_find_hdr() fails. None of them frees or queues the skb, so on that path the caller still owns it.

tcf_ct_act() however funnels every non-zero return into the ownership-transfer exit:

err = tcf_ct_handle_fragments(net, skb, family, p->zone, &defrag);
if (err)
    goto out_frag;
...

out_frag: if (err != -EINPROGRESS) tcf_action_inc_drop_qstats(&c->common); return TC_ACT_CONSUMED;

TC_ACT_CONSUMED means the action took ownership of the skb, so no caller frees it - sch_handle_ingress(), sch_handle_egress() and tcf_qevent_handle() all deliberately skip the free for that verdict. The skb is therefore orphaned: one sk_buff plus its data buffer is leaked per malformed packet, unbounded. Note the drop counter is already incremented for these errors, so the statistics claim a drop that never happens.

Three different ownership states reach out_frag: today - the skb may be queued by the defrag engine (-EINPROGRESS), already freed by nf_ct_handle_fragments(), or still owned by us. Tell the caller which of those it is, and free the packet ourselves in the last case, which restores the TC_ACT_SHOT behaviour that predated the Fixes: commit.

Reproduced on v7.2-rc6 with a 54-byte frame carrying a 40-byte IPv6 header with nexthdr = 0 (hop-by-hop) and nothing after it, on a clsact ingress chain with "action ct". kmemleak reports one leaked 232-byte skbuff_head_cache object plus its 704-byte data buffer per packet; with this patch it reports none.

Severity

7.5 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-74621"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-22T16:16:34Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: act_ct: fix sk_buff leak when the header checks reject a packet\n\ntcf_ct_handle_fragments() runs its header sanity checks before handing\nanything to the defragmentation engine:\n\n\tif (family == NFPROTO_IPV4)\n\t\terr = tcf_ct_ipv4_is_fragment(skb, \u0026frag);\n\telse\n\t\terr = tcf_ct_ipv6_is_fragment(skb, \u0026frag);\n\tif (err || !frag)\n\t\treturn err;\n\ntcf_ct_ipv4_is_fragment() returns -EINVAL or -ENOMEM;\ntcf_ct_ipv6_is_fragment() adds -EPROTO when ipv6_find_hdr() fails. None of\nthem frees or queues the skb, so on that path the caller still owns it.\n\ntcf_ct_act() however funnels every non-zero return into the\nownership-transfer exit:\n\n\terr = tcf_ct_handle_fragments(net, skb, family, p-\u003ezone, \u0026defrag);\n\tif (err)\n\t\tgoto out_frag;\n\t...\nout_frag:\n\tif (err != -EINPROGRESS)\n\t\ttcf_action_inc_drop_qstats(\u0026c-\u003ecommon);\n\treturn TC_ACT_CONSUMED;\n\nTC_ACT_CONSUMED means the action took ownership of the skb, so no caller\nfrees it - sch_handle_ingress(), sch_handle_egress() and\ntcf_qevent_handle() all deliberately skip the free for that verdict. The\nskb is therefore orphaned: one sk_buff plus its data buffer is leaked per\nmalformed packet, unbounded. Note the drop counter is already incremented\nfor these errors, so the statistics claim a drop that never happens.\n\nThree different ownership states reach out_frag: today - the skb may be\nqueued by the defrag engine (-EINPROGRESS), already freed by\nnf_ct_handle_fragments(), or still owned by us. Tell the caller which of\nthose it is, and free the packet ourselves in the last case, which\nrestores the TC_ACT_SHOT behaviour that predated the Fixes: commit.\n\nReproduced on v7.2-rc6 with a 54-byte frame carrying a 40-byte IPv6\nheader with nexthdr = 0 (hop-by-hop) and nothing after it, on a\nclsact ingress chain with \"action ct\". kmemleak reports one leaked\n232-byte skbuff_head_cache object plus its 704-byte data buffer per\npacket; with this patch it reports none.",
  "id": "GHSA-pjmq-j37r-3mm4",
  "modified": "2026-08-25T06:31:23Z",
  "published": "2026-08-22T18:30:27Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-74621"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/23e97d594ddd0153020c506d5041048fbde1beb4"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/439d3e404f9d5e515911cc8132cde198b337c19e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/47d99828591d0fe8be4b9c8992ff3b8e47968db9"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/737873a59905a54ca0d2d127ef882f3f88bf4379"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/8a7ed561671aa6a911a2de99e59ef670a4d0b1df"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b47bb899e04b5407c5a63fe88d4b6676586a6e84"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b5dbecc2016e1692fd1c2532af9c41ba729cb747"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

MSRC_CVE-2026-74621

Vulnerability from csaf_microsoft - Published: 2026-08-24 01:02 - Updated: 2026-08-24 14:46

Summary

net/sched: act_ct: fix sk_buff leak when the header checks reject a packet

Notes

Additional Resources: To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle

Disclaimer: The information provided in the Microsoft Knowledge Base is provided \"as is\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.

CVE-2026-74621

Affected products

Known affected 1 product

Product	Identifier	Version	Remediation
Unresolved product id: 17084-1		—	None Available

References

4 references

URL	Category
https://msrc.microsoft.com/csaf/vex/2026/msrc_cve…	self
https://support.microsoft.com/lifecycle	external
https://www.first.org/cvss	external
https://msrc.microsoft.com/csaf/vex/2026/msrc_cve…	self

JSON

To clipboard

{
  "document": {
    "category": "csaf_vex",
    "csaf_version": "2.0",
    "distribution": {
      "text": "Public",
      "tlp": {
        "label": "WHITE",
        "url": "https://www.first.org/tlp/"
      }
    },
    "lang": "en-US",
    "notes": [
      {
        "category": "general",
        "text": "To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle",
        "title": "Additional Resources"
      },
      {
        "category": "legal_disclaimer",
        "text": "The information provided in the Microsoft Knowledge Base is provided \\\"as is\\\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.",
        "title": "Disclaimer"
      }
    ],
    "publisher": {
      "category": "vendor",
      "contact_details": "secure@microsoft.com",
      "name": "Microsoft Security Response Center",
      "namespace": "https://msrc.microsoft.com"
    },
    "references": [
      {
        "category": "self",
        "summary": "CVE-2026-74621 net/sched: act_ct: fix sk_buff leak when the header checks reject a packet - VEX",
        "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-74621.json"
      },
      {
        "category": "external",
        "summary": "Microsoft Support Lifecycle",
        "url": "https://support.microsoft.com/lifecycle"
      },
      {
        "category": "external",
        "summary": "Common Vulnerability Scoring System",
        "url": "https://www.first.org/cvss"
      }
    ],
    "title": "net/sched: act_ct: fix sk_buff leak when the header checks reject a packet",
    "tracking": {
      "current_release_date": "2026-08-24T14:46:12.000Z",
      "generator": {
        "date": "2026-08-25T07:02:58.280Z",
        "engine": {
          "name": "MSRC Generator",
          "version": "1.0"
        }
      },
      "id": "msrc_CVE-2026-74621",
      "initial_release_date": "2026-08-24T01:02:45.000Z",
      "revision_history": [
        {
          "date": "2026-08-24T01:02:45.000Z",
          "legacy_version": "1",
          "number": "1",
          "summary": "Information published."
        },
        {
          "date": "2026-08-24T14:46:12.000Z",
          "legacy_version": "2",
          "number": "2",
          "summary": "Information published."
        }
      ],
      "status": "final",
      "version": "2"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "branches": [
              {
                "category": "product_version",
                "name": "3.0",
                "product": {
                  "name": "Azure Linux 3.0",
                  "product_id": "17084"
                }
              }
            ],
            "category": "product_name",
            "name": "Azure Linux"
          },
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "azl3 kernel 0:6.6.150.1-1.azl3",
                "product": {
                  "name": "azl3 kernel 0:6.6.150.1-1.azl3",
                  "product_id": "1"
                }
              }
            ],
            "category": "product_name",
            "name": "kernel"
          }
        ],
        "category": "vendor",
        "name": "Microsoft"
      }
    ],
    "relationships": [
      {
        "category": "default_component_of",
        "full_product_name": {
          "name": "azl3 kernel 0:6.6.150.1-1.azl3 as a component of Azure Linux 3.0",
          "product_id": "17084-1"
        },
        "product_reference": "1",
        "relates_to_product_reference": "17084"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2026-74621",
      "notes": [
        {
          "category": "general",
          "text": "Linux",
          "title": "Assigning CNA"
        }
      ],
      "product_status": {
        "known_affected": [
          "17084-1"
        ]
      },
      "references": [
        {
          "category": "self",
          "summary": "CVE-2026-74621 net/sched: act_ct: fix sk_buff leak when the header checks reject a packet - VEX",
          "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-74621.json"
        }
      ],
      "remediations": [
        {
          "category": "none_available",
          "date": "2026-08-24T01:02:45.000Z",
          "details": "There is no fix available for this vulnerability as of now",
          "product_ids": [
            "17084-1"
          ]
        }
      ],
      "title": "net/sched: act_ct: fix sk_buff leak when the header checks reject a packet"
    }
  ]
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

CVE-2026-74621 (GCVE-0-2026-74621)

FKIE_CVE-2026-74621

GHSA-PJMQ-J37R-3MM4

MSRC_CVE-2026-74621

Tags

Sightings

Nomenclature