CVE-2025-40278

In the Linux kernel, the following vulnerability has been resolved: net: sched: act_ife: initialize struct tc_ife to fix KMSAN kernel-infoleak Fix a KMSAN kernel-infoleak detected by the syzbot . [net?] KMSAN: kernel-infoleak in __skb_datagram_iter In tcf_ife_dump(), the variable 'opt' was partially initialized using a designatied initializer. While the padding bytes are reamined uninitialized. nla_put() copies the entire structure into a netlink message, these uninitialized bytes leaked to userspace. Initialize the structure with memset before assigning its fields to ensure all members and padding are cleared prior to beign copied. This change silences the KMSAN report and prevents potential information leaks from the kernel memory. This fix has been tested and validated by syzbot. This patch closes the bug reported at the following syzkaller link and ensures no infoleak.

Package Linux Kernel
Published 2025-12-06
Last modified 2026-06-02
Patch available
Yes

Affected versions

Linux kernel versions 4.6 and later are affected. Fixed in 5.4.302, 5.10.247, 5.15.197, 6.1.159, 6.6.117, 6.12.59, 6.17.9, 6.18 and their respective stable series.

Affected from
≥ 4.6
Fixed in
✓ 5.4.302 5.4.x ✓ 5.10.247 5.10.x ✓ 5.15.197 5.15.x ✓ 6.1.159 6.1.x ✓ 6.6.117 6.6.x ✓ 6.12.59 6.12.x ✓ 6.17.9 6.17.x ✓ 6.18

References

The following references provide additional information about CVE-2025-40278 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Frequently asked questions

  • What is CVE-2025-40278?

    CVE-2025-40278 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 4.6 onward and has been patched in 5.4.302, 5.10.247, 5.15.197 and others. CVE-2025-40278 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • Is there a patch available for CVE-2025-40278?

    Yes — CVE-2025-40278 has been patched. Fixed versions include 5.4.302, 5.10.247, 5.15.197 and others. If you are running Linux kernel 4.6 or later up to the fix versions, apply the relevant patch for your kernel branch.

  • Is CVE-2025-40278 actively exploited?

    No — CVE-2025-40278 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.