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FKIE_CVE-2026-89565

Vulnerability from fkie_nvd - Published: 2026-09-11 20:19 - Updated: 2026-09-14 13:19
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved: ipip: fix skb leak in collect_md mode when metadata_dst allocation fails In collect_md mode ipip_tunnel_rcv() returns 0 without freeing the skb when ip_tun_rx_dst() fails to allocate the metadata_dst. ipip_rcv() and mplsip_rcv() are registered as xfrm_tunnel handlers, so tunnel4_rcv() and tunnelmpls4_rcv() read the zero return as "the packet has been consumed" and do not free it either. The skb is leaked. The other tunnel drivers all dispose of the packet at this point: ip6_tunnel.c jumps to its drop label, ip_gre.c and ip6_gre.c return PACKET_REJECT, which makes gre_rcv() free the skb. Only ipip returns 0. Jump to the existing drop label instead. It frees the skb and still returns 0, so the packet keeps being reported as consumed, which is what we want here: the outer header has already been pulled, and neither the remaining handlers nor an ICMP unreachable have any use for it. Triggering this needs an ipip or mplsip tunnel in collect_md mode and an atomic allocation failure, which is why it has gone unnoticed.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/1909df2d066424767429e13053eb9701263430ef
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/31e4be21dacee49395013caae28576484a049a4f
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/6776efe4a52f289a3fc18f8adf19b035a7d8e1bb
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/6d8c5b266d0035a061573843a7243be068eb6118
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/c4dc23de4cc75e4e304170b31bb8aeeacd5cb990
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/fd01f1a3ed4a189a784654f7c69eb565872f2e12
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/ipv4/ipip.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "1909df2d066424767429e13053eb9701263430ef",
              "status": "affected",
              "version": "cfc7381b3002756b1dcada32979e942aa3126e31",
              "versionType": "git"
            },
            {
              "lessThan": "c4dc23de4cc75e4e304170b31bb8aeeacd5cb990",
              "status": "affected",
              "version": "cfc7381b3002756b1dcada32979e942aa3126e31",
              "versionType": "git"
            },
            {
              "lessThan": "6d8c5b266d0035a061573843a7243be068eb6118",
              "status": "affected",
              "version": "cfc7381b3002756b1dcada32979e942aa3126e31",
              "versionType": "git"
            },
            {
              "lessThan": "31e4be21dacee49395013caae28576484a049a4f",
              "status": "affected",
              "version": "cfc7381b3002756b1dcada32979e942aa3126e31",
              "versionType": "git"
            },
            {
              "lessThan": "fd01f1a3ed4a189a784654f7c69eb565872f2e12",
              "status": "affected",
              "version": "cfc7381b3002756b1dcada32979e942aa3126e31",
              "versionType": "git"
            },
            {
              "lessThan": "6776efe4a52f289a3fc18f8adf19b035a7d8e1bb",
              "status": "affected",
              "version": "cfc7381b3002756b1dcada32979e942aa3126e31",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/ipv4/ipip.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.9"
            },
            {
              "lessThan": "4.9",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.188",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.157",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.109",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.50",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3-rc1",
              "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\nipip: fix skb leak in collect_md mode when metadata_dst allocation fails\n\nIn collect_md mode ipip_tunnel_rcv() returns 0 without freeing the skb\nwhen ip_tun_rx_dst() fails to allocate the metadata_dst. ipip_rcv() and\nmplsip_rcv() are registered as xfrm_tunnel handlers, so tunnel4_rcv()\nand tunnelmpls4_rcv() read the zero return as \"the packet has been\nconsumed\" and do not free it either. The skb is leaked.\n\nThe other tunnel drivers all dispose of the packet at this point:\nip6_tunnel.c jumps to its drop label, ip_gre.c and ip6_gre.c return\nPACKET_REJECT, which makes gre_rcv() free the skb. Only ipip returns 0.\n\nJump to the existing drop label instead. It frees the skb and still\nreturns 0, so the packet keeps being reported as consumed, which is what\nwe want here: the outer header has already been pulled, and neither the\nremaining handlers nor an ICMP unreachable have any use for it.\n\nTriggering this needs an ipip or mplsip tunnel in collect_md mode and an\natomic allocation failure, which is why it has gone unnoticed."
    }
  ],
  "id": "CVE-2026-89565",
  "lastModified": "2026-09-14T13:19:11.600",
  "metrics": {},
  "published": "2026-09-11T20:19:40.427",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/1909df2d066424767429e13053eb9701263430ef"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/31e4be21dacee49395013caae28576484a049a4f"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/6776efe4a52f289a3fc18f8adf19b035a7d8e1bb"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/6d8c5b266d0035a061573843a7243be068eb6118"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/c4dc23de4cc75e4e304170b31bb8aeeacd5cb990"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/fd01f1a3ed4a189a784654f7c69eb565872f2e12"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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