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tunnels: do not assume transport header in iptunnel_pmtud_check_icmp()

Type: advisorySource: Official CVE List1 source record

In the Linux kernel, the following vulnerability has been resolved: tunnels: do not assume transport header in iptunnel_pmtud_check_icmp() In some cases, iptunnel_pmtud_check_icmp() can be called while skb transport header is not set. This triggers an out-of-bound access, because (typeof(skb->transport_header))~0U is 65535. Access the icmp header based on IPv4 network header, after making sure icmp->type is present in skb linear part. Note that iptunnel_pmtud_check_icmpv6()) is fine.

Announced Source revision 1
Original source ↗

CVE-2026-63992

Primary source · Revision 1

Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.

Security context

Source reference: cve:CVE-2026-63992

Linux

Source reference: /containers/cna/affected/0/product

Affected versions
Not stated in this record
Fixed versions
Not stated in this record
Prerequisites
Not stated in this record

Linux

Source reference: /containers/cna/affected/1/product

Affected versions
Not stated in this record
Fixed versions
Not stated in this record
Prerequisites
Not stated in this record

Structured affected-version data

Original package identities and version rules from this source.

[
  {
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "vendor": "Linux",
    "product": "Linux",
    "versions": [
      {
        "status": "affected",
        "version": "4cb47a8644cc9eb8ec81190a50e79e6530d0297f",
        "lessThan": "5a92cb45e34749865d03daf8d3500f77b5f6644c",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "4cb47a8644cc9eb8ec81190a50e79e6530d0297f",
        "lessThan": "c7b7ec3e69e673c0d6b57f74d21da50c485c598e",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "4cb47a8644cc9eb8ec81190a50e79e6530d0297f",
        "lessThan": "7f4f7efe7f30edd29c4988de01728bf2398217e4",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "4cb47a8644cc9eb8ec81190a50e79e6530d0297f",
        "lessThan": "e917d0c69f01af2bb4fbea2b66d560a53b3ac7ec",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "4cb47a8644cc9eb8ec81190a50e79e6530d0297f",
        "lessThan": "a096b6e34f602950af9a2b0856cd93a5f4c276d7",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "4cb47a8644cc9eb8ec81190a50e79e6530d0297f",
        "lessThan": "43368636c663cff6e59dde93cf4b8e43ac28eb93",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "4cb47a8644cc9eb8ec81190a50e79e6530d0297f",
        "lessThan": "cb549df9ce4ee15c9d5b19ddab12cf2128e4313c",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "4cb47a8644cc9eb8ec81190a50e79e6530d0297f",
        "lessThan": "509323077ef79a26ba0c60bb556e45c12c398b2d",
        "versionType": "git"
      }
    ],
    "programFiles": [
      "net/ipv4/ip_tunnel_core.c"
    ],
    "defaultStatus": "unaffected"
  },
  {
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "vendor": "Linux",
    "product": "Linux",
    "versions": [
      {
        "status": "affected",
        "version": "5.9"
      },
      {
        "status": "unaffected",
        "version": "0",
        "lessThan": "5.9",
        "versionType": "semver"
      },
      {
        "status": "unaffected",
        "version": "5.10.259",
        "versionType": "semver",
        "lessThanOrEqual": "5.10.*"
      },
      {
        "status": "unaffected",
        "version": "5.15.210",
        "versionType": "semver",
        "lessThanOrEqual": "5.15.*"
      },
      {
        "status": "unaffected",
        "version": "6.1.176",
        "versionType": "semver",
        "lessThanOrEqual": "6.1.*"
      },
      {
        "status": "unaffected",
        "version": "6.6.143",
        "versionType": "semver",
        "lessThanOrEqual": "6.6.*"
      },
      {
        "status": "unaffected",
        "version": "6.12.93",
        "versionType": "semver",
        "lessThanOrEqual": "6.12.*"
      },
      {
        "status": "unaffected",
        "version": "6.18.35",
        "versionType": "semver",
        "lessThanOrEqual": "6.18.*"
      },
      {
        "status": "unaffected",
        "version": "7.0.12",
        "versionType": "semver",
        "lessThanOrEqual": "7.0.*"
      },
      {
        "status": "unaffected",
        "version": "7.1",
        "versionType": "original_commit_for_fix",
        "lessThanOrEqual": "*"
      }
    ],
    "programFiles": [
      "net/ipv4/ip_tunnel_core.c"
    ],
    "defaultStatus": "affected"
  }
]
Related CVEs
CVE-2026-63992

Source reference: /cveMetadata/cveId

Publisher severity

critical

Source reference: /containers/cna/metrics

Event
#40921 · Revision 1
Added to Heist Feed
Publisher date
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