GHSA-FGX8-R5G7-5CR9
Vulnerability from github – Published: 2026-06-03 18:33 – Updated: 2026-06-05 09:33In the Linux kernel, the following vulnerability has been resolved:
netfilter: nft_inner: Fix IPv6 inner_thoff desync
In nft_inner_parse_l2l3(), when processing inner IPv6 packets, ipv6_find_hdr() correctly computes the transport header offset traversing all extension headers, but the result is immediately overwritten with nhoff + sizeof(_ip6h) (40 bytes), which only accounts for the IPv6 base header. This creates a desync between inner_thoff (wrong — points to extension header start) and l4proto (correct — e.g., IPPROTO_TCP), enabling transport header forgery and potential firewall bypass. This issue affects stable versions from Linux 6.2.
For comparison, the normal (non-inner) IPv6 path correctly preserves ipv6_find_hdr()'s result. Removing the incorrect overwrite ensures that ipv6_find_hdr()'s calculated transport header offset is preserved, thereby fixing the desynchronization.
{
"affected": [],
"aliases": [
"CVE-2026-46244"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-06-03T18:16:24Z",
"severity": "CRITICAL"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nft_inner: Fix IPv6 inner_thoff desync\n\nIn nft_inner_parse_l2l3(), when processing inner IPv6 packets,\nipv6_find_hdr() correctly computes the transport header offset\ntraversing all extension headers, but the result is immediately\noverwritten with nhoff + sizeof(_ip6h) (40 bytes), which only\naccounts for the IPv6 base header. This creates a desync between\ninner_thoff (wrong \u2014 points to extension header start) and l4proto\n(correct \u2014 e.g., IPPROTO_TCP), enabling transport header forgery\nand potential firewall bypass. This issue affects stable versions\nfrom Linux 6.2.\n\nFor comparison, the normal (non-inner) IPv6 path correctly\npreserves ipv6_find_hdr()\u0027s result. Removing the incorrect overwrite\nensures that ipv6_find_hdr()\u0027s calculated transport header offset is\npreserved, thereby fixing the desynchronization.",
"id": "GHSA-fgx8-r5g7-5cr9",
"modified": "2026-06-05T09:33:46Z",
"published": "2026-06-03T18:33:12Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-46244"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/689bbf48c1f45130086ae1c46ab83ea4c753c601"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/870d59e2cf218e7418491e26bad768cb16654582"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/b6a91f68ebfed9c38e0e9150f58a9b85da07181c"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/c161ad9157f5a0429b5ff94d9770faf3bf48d273"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/d0f98a3617f6ae5b1e95cde1e68e7ead4a1279ce"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
"type": "CVSS_V3"
}
]
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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- Confirmed: The vulnerability has been validated from an analyst's perspective.
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- 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.