CVE-2026-31495
In the Linux kernel, the following vulnerability has been resolved: netfilter: ctnetlink: use netlink policy range checks Replace manual range and mask validations with netlink policy annotations in ctnetlink code paths, so that the netlink core rejects…
Does this matter?
Lower severity and a low EPSS score (0.13%). Track it; it rarely justifies an emergency change on its own.
Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: ctnetlink: use netlink policy range checks Replace manual range and mask validations with netlink policy annotations in ctnetlink code paths, so that the netlink core rejects invalid values early and can generate extack errors. - CTA_PROTOINFO_TCP_STATE: reject values > TCP_CONNTRACK_SYN_SENT2 at policy level, removing the manual >= TCP_CONNTRACK_MAX check. - CTA_PROTOINFO_TCP_WSCALE_ORIGINAL/REPLY: reject values > TCP_MAX_WSCALE (14). The normal TCP option parsing path already clamps to this value, but the ctnetlink path accepted 0-255, causing undefined behavior when used as a u32 shift count. - CTA_FILTER_ORIG_FLAGS/REPLY_FLAGS: use NLA_POLICY_MASK with CTA_FILTER_F_ALL, removing the manual mask checks. - CTA_EXPECT_FLAGS: use NLA_POLICY_MASK with NF_CT_EXPECT_MASK, adding a new mask define grouping all valid expect flags. Extracted from a broader nf-next patch by Florian Westphal, scoped to ctnetlink for the fixes tree.
- CVSS 3.1
- 5.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.13% probability · 3th percentile
- CISA KEV
- Not listed
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/2ef71307c86a9f866d6e28f1a0c06e2e9d794474Patch
- https://git.kernel.org/stable/c/435b576cd2faa75154777868f8cbb73bf71644d3Patch
- https://git.kernel.org/stable/c/45c33e79ae705b7af97e3117672b6cd258dd0b1bPatch
- https://git.kernel.org/stable/c/4f7d25f3f0786402ba48ff7d13b6241d77d975f5Patch
- https://git.kernel.org/stable/c/675c913b940488a84effdeeac5a1cfb657b59804Patch
- https://git.kernel.org/stable/c/8f15b5071b4548b0aafc03b366eb45c9c6566704Patch
- https://git.kernel.org/stable/c/c6cb41eaae875501eaaa487b8db6539feb092292Patch
- https://git.kernel.org/stable/c/fcec5ce2d73a41668b24e3f18c803541602a59f6Patch
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html
- https://cert-portal.siemens.com/productcert/html/ssa-082556.html
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.