CVE-2025-40078 Affecting kernel-default-base package, versions <6.12.0-160000.6.1.160000.2.4


Severity

Recommended
0.0
medium
0
10

Based on SUSE Linux Enterprise Server security rating.

Threat Intelligence

EPSS
0.04% (10th percentile)

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  • Snyk IDSNYK-SLES1600-KERNELDEFAULTBASE-14381292
  • published11 Dec 2025
  • disclosed26 Nov 2025

Introduced: 26 Nov 2025

NewCVE-2025-40078  (opens in a new tab)

How to fix?

Upgrade SLES:16.0.0 kernel-default-base to version 6.12.0-160000.6.1.160000.2.4 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream kernel-default-base package and not the kernel-default-base package as distributed by SLES. See How to fix? for SLES:16.0.0 relevant fixed versions and status.

In the Linux kernel, the following vulnerability has been resolved:

bpf: Explicitly check accesses to bpf_sock_addr

Syzkaller found a kernel warning on the following sock_addr program:

0: r0 = 0
1: r2 = *(u32 *)(r1 +60)
2: exit

which triggers:

verifier bug: error during ctx access conversion (0)

This is happening because offset 60 in bpf_sock_addr corresponds to an implicit padding of 4 bytes, right after msg_src_ip4. Access to this padding isn't rejected in sock_addr_is_valid_access and it thus later fails to convert the access.

This patch fixes it by explicitly checking the various fields of bpf_sock_addr in sock_addr_is_valid_access.

I checked the other ctx structures and is_valid_access functions and didn't find any other similar cases. Other cases of (properly handled) padding are covered in new tests in a subsequent patch.

CVSS Base Scores

version 3.1