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