CVE-2024-26849: netlink: add nla be16/32 types to minlen array

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-04-17 · updated 2026-06-17
Weakness: CWE-908

Description

In the Linux kernel, the following vulnerability has been resolved: netlink: add nla be16/32 types to minlen array BUG: KMSAN: uninit-value in nla_validate_range_unsigned lib/nlattr.c:222 [inline] BUG: KMSAN: uninit-value in nla_validate_int_range lib/nlattr.c:336 [inline] BUG: KMSAN: uninit-value in validate_nla lib/nlattr.c:575 [inline] BUG: KMSAN: uninit-value in __nla_validate_parse+0x2e20/0x45c0 lib/nlattr.c:631 nla_validate_range_unsigned lib/nlattr.c:222 [inline] nla_validate_int_range lib/nlattr.c:336 [inline] validate_nla lib/nlattr.c:575 [inline] ... The message in question matches this policy: [NFTA_TARGET_REV] = NLA_POLICY_MAX(NLA_BE32, 255), but because NLA_BE32 size in minlen array is 0, the validation code will read past the malformed (too small) attribute. Note: Other attributes, e.g. BITFIELD32, SINT, UINT.. are also missing: those likely should be added too.

Affected products

Linux kernel: from 6.1 before 6.1.81; from 6.2 before 6.6.21; from 6.7 before 6.7.9; 6.8-rc1, 6.8-rc2, 6.8-rc3, 6.8-rc4, 6.8-rc5, 6.8-rc6 — fixed in 6.1.81, 6.6.21, 6.7.9

How to fix

Upgrade to a fixed version: Linux kernel 6.1.81, 6.6.21, 6.7.9. Check the vendor advisory for mitigations.

References

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