CVE-2026-46244
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…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.32%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 9.1 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
- EPSS
- 0.32% probability · 25th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-823
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/689bbf48c1f45130086ae1c46ab83ea4c753c601Patch
- https://git.kernel.org/stable/c/870d59e2cf218e7418491e26bad768cb16654582Patch
- https://git.kernel.org/stable/c/b6a91f68ebfed9c38e0e9150f58a9b85da07181cPatch
- https://git.kernel.org/stable/c/c161ad9157f5a0429b5ff94d9770faf3bf48d273Patch
- https://git.kernel.org/stable/c/d0f98a3617f6ae5b1e95cde1e68e7ead4a1279cePatch
- https://access.redhat.com/errata/RHSA-2026:33215
- https://access.redhat.com/errata/RHSA-2026:34094
- https://access.redhat.com/errata/RHSA-2026:34443
- https://access.redhat.com/errata/RHSA-2026:34911
- https://access.redhat.com/errata/RHSA-2026:36018
- https://access.redhat.com/errata/RHSA-2026:55618
- https://access.redhat.com/errata/RHSA-2026:55763
- https://access.redhat.com/errata/RHSA-2026:56225
- https://access.redhat.com/security/cve/CVE-2026-46244
- https://bugzilla.redhat.com/show_bug.cgi?id=2484451
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-46244.json
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.