CVE-2025-40236

CVE-2025-40236 is a security vulnerability that is still awaiting full analysis and scoring. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Description

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.

Frequently asked questions

What is 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.
Is CVE-2025-40236 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (6th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2025-40236?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-40236 have an EU (EUVD) identifier?
Yes. CVE-2025-40236 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-201223.
When was CVE-2025-40236 published?
CVE-2025-40236 was published on 2025-12-04 and last updated on 2026-06-17.

References