Skip to content
Heist/ feed
Critical

seg6: separate dst_cache for input and output paths in seg6 lwtunnel

Type: advisorySource: Official CVE List1 source record

In the Linux kernel, the following vulnerability has been resolved: seg6: separate dst_cache for input and output paths in seg6 lwtunnel The seg6 lwtunnel uses a single dst_cache per encap route, shared between seg6_input_core() and seg6_output_core(). These two paths can perform the post-encap SID lookup in different routing contexts (e.g., ip rules matching on the ingress interface, or VRF table separation). Whichever path runs first populates the cache, and the other reuses it blindly, bypassing its own lookup. Fix this by splitting the cache into cache_input and cache_output, so each path maintains its own cached dst independently.

Announced Source revision 1
Original source ↗

CVE-2026-31668

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-2026-31668

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": "6c8702c60b88651072460f3f4026c7dfe2521d12",
        "lessThan": "1dec91d3b1cefb82635761b7812154af3ef46449",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "6c8702c60b88651072460f3f4026c7dfe2521d12",
        "lessThan": "750569d6987a0ff46317a4b86eb3907e296287bf",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "6c8702c60b88651072460f3f4026c7dfe2521d12",
        "lessThan": "57d0374d14fa667dec6952173b93e7e84486d5c9",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "6c8702c60b88651072460f3f4026c7dfe2521d12",
        "lessThan": "84d458018b147176b259347103fccb7e93abd2b1",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "6c8702c60b88651072460f3f4026c7dfe2521d12",
        "lessThan": "6305ad032b03d2ea4181b953a66e19a9a6ed053c",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "6c8702c60b88651072460f3f4026c7dfe2521d12",
        "lessThan": "fb56de5d99218de49d5d43ef3a99e062ecd0f9a1",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "6c8702c60b88651072460f3f4026c7dfe2521d12",
        "lessThan": "17d87d42874f5d6c1a0ccc6d9190dfe82a9a7a6a",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "6c8702c60b88651072460f3f4026c7dfe2521d12",
        "lessThan": "c3812651b522fe8437ebb7063b75ddb95b571643",
        "versionType": "git"
      }
    ],
    "programFiles": [
      "net/ipv6/seg6_iptunnel.c"
    ],
    "defaultStatus": "unaffected"
  },
  {
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "vendor": "Linux",
    "product": "Linux",
    "versions": [
      {
        "status": "affected",
        "version": "4.10"
      },
      {
        "status": "unaffected",
        "version": "0",
        "lessThan": "4.10",
        "versionType": "semver"
      },
      {
        "status": "unaffected",
        "version": "5.10.253",
        "versionType": "semver",
        "lessThanOrEqual": "5.10.*"
      },
      {
        "status": "unaffected",
        "version": "5.15.203",
        "versionType": "semver",
        "lessThanOrEqual": "5.15.*"
      },
      {
        "status": "unaffected",
        "version": "6.1.169",
        "versionType": "semver",
        "lessThanOrEqual": "6.1.*"
      },
      {
        "status": "unaffected",
        "version": "6.6.135",
        "versionType": "semver",
        "lessThanOrEqual": "6.6.*"
      },
      {
        "status": "unaffected",
        "version": "6.12.82",
        "versionType": "semver",
        "lessThanOrEqual": "6.12.*"
      },
      {
        "status": "unaffected",
        "version": "6.18.23",
        "versionType": "semver",
        "lessThanOrEqual": "6.18.*"
      },
      {
        "status": "unaffected",
        "version": "6.19.13",
        "versionType": "semver",
        "lessThanOrEqual": "6.19.*"
      },
      {
        "status": "unaffected",
        "version": "7.0",
        "versionType": "original_commit_for_fix",
        "lessThanOrEqual": "*"
      }
    ],
    "programFiles": [
      "net/ipv6/seg6_iptunnel.c"
    ],
    "defaultStatus": "affected"
  }
]
Related CVEs
CVE-2026-31668

Source reference: /cveMetadata/cveId

Publisher severity

critical

Source reference: /containers/cna/metrics

Event
#39945 · Revision 1
Added to Heist Feed
Publisher date
Read the original announcement