CVE-2025-40236

In the Linux kernel, the following vulnerability has been resolved: virtio-net: zero unused hash fields When GSO tunnel is negotiated virtio_net_hdr_tnl_from_skb() tries to initialize the tunnel metadata but forget to zero unused rxhash fields. This may leak information to another side. Fixing this by zeroing the unused hash fields.

Package Linux Kernel
Published 2025-12-04
Last modified 2026-04-15
Patch available
Yes

Affected versions

Linux kernel versions 6.17 and later are affected. Fixed in 6.17.6, 6.18 and their respective stable series.

Affected from
≥ 6.17
Fixed in
✓ 6.17.6 6.17.x ✓ 6.18

References

The following references provide additional information about CVE-2025-40236 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-2025-40236?

    CVE-2025-40236 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 6.17 onward and has been patched in 6.17.6 and 6.18. CVE-2025-40236 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • Is there a patch available for CVE-2025-40236?

    Yes — CVE-2025-40236 has been patched. Fixed versions include 6.17.6 and 6.18. If you are running Linux kernel 6.17 or later up to the fix versions, apply the relevant patch for your kernel branch.

  • Is CVE-2025-40236 actively exploited?

    No — CVE-2025-40236 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.