CVE-2026-98899 (GCVE-0-2026-98899)

Vulnerability from cvelistv5 – Published: 2026-10-23 11:54 – Updated: 2026-10-26 06:56
VLAI
Title
netfilter: ipset: mark the rcu locked areas properly
Summary
In the Linux kernel, the following vulnerability has been resolved: netfilter: ipset: mark the rcu locked areas properly When we bump the uref counter, there's no need to keep the rcu lock because the referred hash table can't disappear. Also, from the same reason in mtype_gc we need the rcu lock and not a spinlock.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6653 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: f66ee0410b1c3481ee75e5db9b34547b4d582465 , < 67bd3d2350d17c2f4fb158c3f917c10b15ecbc94 (git)
Affected: f66ee0410b1c3481ee75e5db9b34547b4d582465 , < 892399abd1a005a455d5b74d86d82b9773405f2b (git)
Affected: f66ee0410b1c3481ee75e5db9b34547b4d582465 , < eee5172741b2c0e73210020732043e5d589295d3 (git)
Affected: f66ee0410b1c3481ee75e5db9b34547b4d582465 , < ecb48c6b9edc78de8dd456c365727ae14b88c1ee (git)
Affected: f66ee0410b1c3481ee75e5db9b34547b4d582465 , < 0c46c9ce24130657ec7460c27fba5d445f5abd06 (git)
Affected: f66ee0410b1c3481ee75e5db9b34547b4d582465 , < ca9fab1ca15534cef1630e81a479e94b3bbcdb6a (git)
Affected: f66ee0410b1c3481ee75e5db9b34547b4d582465 , < 5d0c22e73656d050daffad10a2ba8765ce8441c8 (git)
Affected: 5dd9488ae41070b69d2f4acb580f77db5705f9ca (git)
Affected: a469bab3386aebff33c59506f3a95e35b91118fd (git)
Affected: 5.4.24 , < 5.5 (semver)
Affected: 5.5.8 , < 5.6 (semver)
guessed Create a notification for this product.
Linux Linux Affected: 5.6
Unaffected: 0 , < 5.6 (semver)
Unaffected: 5.10.271 , ≤ 5.10.* (semver)
Unaffected: 5.15.222 , ≤ 5.15.* (semver)
Unaffected: 6.1.189 , ≤ 6.1.* (semver)
Unaffected: 6.6.158 , ≤ 6.6.* (semver)
Unaffected: 6.12.111 , ≤ 6.12.* (semver)
Unaffected: 6.18.53 , ≤ 6.18.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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{
  "containers": {
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          "product": "Linux",
          "programFiles": [
            "net/netfilter/ipset/ip_set_hash_gen.h"
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              "version": "7.2",
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          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: ipset: mark the rcu locked areas properly\n\nWhen we bump the uref counter, there\u0027s no need to keep\nthe rcu lock because the referred hash table can\u0027t\ndisappear. Also, from the same reason in mtype_gc we\nneed the rcu lock and not a spinlock."
        }
      ],
      "metrics": [
        {
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            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The attacker must send local NETLINK_NETFILTER IPSET_CMD_CREATE/ADD messages: ip_set_create() starts timeout GC, while ip_set_uadd()-\u003eip_set_ad()-\u003ecall_ad()-\u003emtype_add() triggers mtype_resize(). Received packets cannot invoke the userspace-only resize path.\nAC:L - The same attacker chooses IPSET_ATTR_TIMEOUT, INITVAL, BUCKETSIZE, and colliding elements, repeatedly causing scheduled mtype_gc() to race attacker-triggered mtype_resize(); no victim-controlled state or hardware failure is required.\nPR:L - nfnetlink_rcv() requires netlink_net_capable(skb, CAP_NET_ADMIN), but this checks sock_net(skb-\u003esk)-\u003euser_ns; an unprivileged user can obtain that capability in a new user and network namespace, where ipset state is per-netns.\nUI:N - The attacker creates the timeout set, sends the IPSET_CMD_ADD messages, and lets its scheduled mtype_gc() work execute; no action by another user is required.\nS:U - The stale htable access in mtype_gc() corrupts kernel heap memory within the same host-kernel security authority; it does not cross a guest-host, IOMMU, or comparable scope boundary.\nC:H - If mtype_resize() frees orig before mtype_gc() pins it, mtype_gc_do() follows reclaimed t-\u003ehregion and bucket pointers and processes freed entries; this exploitable htable use-after-free permits kernel-memory disclosure.\nI:H - The stale path increments and decrements freed t-\u003euref, locks and updates freed t-\u003ehregion data, clears or frees buckets in mtype_gc_do(), and may call mtype_ahash_destroy() again, yielding kernel-heap write and free primitives suitable for code execution.\nA:H - The use-after-free can dereference or spin-lock freed t-\u003ehregion and bucket memory, or free the stale table again through mtype_ahash_destroy(), causing an oops, panic, or hang."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-26T06:56:26.708Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
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          "url": "https://git.kernel.org/stable/c/67bd3d2350d17c2f4fb158c3f917c10b15ecbc94"
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          "url": "https://git.kernel.org/stable/c/892399abd1a005a455d5b74d86d82b9773405f2b"
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        {
          "url": "https://git.kernel.org/stable/c/ca9fab1ca15534cef1630e81a479e94b3bbcdb6a"
        },
        {
          "url": "https://git.kernel.org/stable/c/5d0c22e73656d050daffad10a2ba8765ce8441c8"
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      "title": "netfilter: ipset: mark the rcu locked areas properly",
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    "assignerShortName": "Linux",
    "cveId": "CVE-2026-98899",
    "datePublished": "2026-10-23T11:54:09.249Z",
    "dateReserved": "2026-09-25T10:25:14.379Z",
    "dateUpdated": "2026-10-26T06:56:26.708Z",
    "state": "PUBLISHED"
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  "dataVersion": "5.2",
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      "date": "2026-11-08",
      "epss": "0.00169",
      "percentile": "0.06344"
    },
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      "cve": "CVE-2026-98899",
      "id": "msrc_CVE-2026-98899",
      "initial_release_date": "2026-10-24T01:04:52.000Z",
      "product_status:fixed": "1",
      "product_status:known_affected": "1",
      "product_status:under_investigation": "1",
      "source": "Microsoft CSAF VEX",
      "status": "final",
      "title": "netfilter: ipset: mark the rcu locked areas properly",
      "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-98899.json",
      "version": "4"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
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                "product": "Linux",
                "programFiles": [
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                ],
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                "vendor": "Linux",
                "versions": [
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          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: ipset: mark the rcu locked areas properly\n\nWhen we bump the uref counter, there\u0027s no need to keep\nthe rcu lock because the referred hash table can\u0027t\ndisappear. Also, from the same reason in mtype_gc we\nneed the rcu lock and not a spinlock."
          }
        ],
        "id": "CVE-2026-98899",
        "lastModified": "2026-10-26T07:17:15.190",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "LOCAL",
                "availabilityImpact": "HIGH",
                "baseScore": 7.8,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "HIGH",
                "integrityImpact": "HIGH",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 1.8,
              "impactScore": 5.9,
              "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
              "type": "Secondary"
            }
          ]
        },
        "published": "2026-10-23T12:18:23.897",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/0c46c9ce24130657ec7460c27fba5d445f5abd06"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/5d0c22e73656d050daffad10a2ba8765ce8441c8"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/67bd3d2350d17c2f4fb158c3f917c10b15ecbc94"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/892399abd1a005a455d5b74d86d82b9773405f2b"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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            "url": "https://git.kernel.org/stable/c/eee5172741b2c0e73210020732043e5d589295d3"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Received"
      }
    },
    "suse_vex": {
      "aggregate_severity": "important",
      "current_release_date": "2026-10-27T00:42:56Z",
      "cve": "CVE-2026-98899",
      "id": "CVE-2026-98899",
      "initial_release_date": "2026-10-23T23:53:45Z",
      "product_status:known_affected": "158",
      "product_status:known_not_affected": "190",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-98899",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/2026/cve-2026-98899.json",
      "version": "4"
    }
  }
}



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Tags
Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

JSON
How durations are calculated

Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.

Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.

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    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.