CVE-2026-31495

MEDIUM EPSS 2.4%
Published Apr 22, 20262mo ago · Modified Jun 17, 20261w ago
5.5 CVSS 3.1
Medium
Find Similar
Published Apr 22, 2026 2mo ago
Last Modified Jun 17, 2026 1w ago

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 Details

Base Score
5.5
Exploitability
1.8
Impact
3.6
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High

Threat Intelligence

EPSS Exploit Probability
2.4% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Affected Products 15

VendorProductVersionRange
linuxlinux_kernel*≥2.6.22.1  –  <5.10.253
linuxlinux_kernel*≥5.11  –  <5.15.203
linuxlinux_kernel*≥5.16  –  <6.1.168
linuxlinux_kernel*≥6.2  –  <6.6.131
linuxlinux_kernel*≥6.7  –  <6.12.80
linuxlinux_kernel*≥6.13  –  <6.18.21
linuxlinux_kernel*≥6.19  –  <6.19.11
linuxlinux_kernel2.6.22any
linuxlinux_kernel7.0any
linuxlinux_kernel7.0any
linuxlinux_kernel7.0any
linuxlinux_kernel7.0any
linuxlinux_kernel7.0any
linuxlinux_kernel7.0any
linuxlinux_kernel7.0any

References 8

  • git.kernel.org https://git.kernel.org/stable/c/2ef71307c86a9f866d6e28f1a0c06e2e9d794474
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/435b576cd2faa75154777868f8cbb73bf71644d3
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/45c33e79ae705b7af97e3117672b6cd258dd0b1b
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/4f7d25f3f0786402ba48ff7d13b6241d77d975f5
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/675c913b940488a84effdeeac5a1cfb657b59804
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/8f15b5071b4548b0aafc03b366eb45c9c6566704
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/c6cb41eaae875501eaaa487b8db6539feb092292
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/fcec5ce2d73a41668b24e3f18c803541602a59f6
    Patch

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/2ef71307c86a9f866d6e28f1a0c06e2e9d794474
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/435b576cd2faa75154777868f8cbb73bf71644d3
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/45c33e79ae705b7af97e3117672b6cd258dd0b1b
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/4f7d25f3f0786402ba48ff7d13b6241d77d975f5
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/675c913b940488a84effdeeac5a1cfb657b59804
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/8f15b5071b4548b0aafc03b366eb45c9c6566704
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/c6cb41eaae875501eaaa487b8db6539feb092292
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/fcec5ce2d73a41668b24e3f18c803541602a59f6
    Patch