CVE-2026-46244

CRITICAL

netfilter: nft_inner: Fix IPv6 inner_thoff desync

Title source: cna
STIX 2.1

Description

In 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.

Scores

CVSS v3 9.1
EPSS 0.0004
EPSS Percentile 13.2%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Details

Status published
Products (14)
Linux/Linux < 6.2
Linux/Linux 3a07327d10a09379315c844c63f27941f5081e0a - 689bbf48c1f45130086ae1c46ab83ea4c753c601
Linux/Linux 3a07327d10a09379315c844c63f27941f5081e0a - 870d59e2cf218e7418491e26bad768cb16654582
Linux/Linux 3a07327d10a09379315c844c63f27941f5081e0a - b6a91f68ebfed9c38e0e9150f58a9b85da07181c
Linux/Linux 3a07327d10a09379315c844c63f27941f5081e0a - c161ad9157f5a0429b5ff94d9770faf3bf48d273
Linux/Linux 3a07327d10a09379315c844c63f27941f5081e0a - d0f98a3617f6ae5b1e95cde1e68e7ead4a1279ce
Linux/Linux 6.12.92 - 6.12.*
Linux/Linux 6.18.34 - 6.18.*
Linux/Linux 6.2
Linux/Linux 6.6.142 - 6.6.*
... and 4 more
Published Jun 03, 2026
Tracked Since Jun 03, 2026