CVE-2025-21669

CVE-2025-21669 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-476.

Key facts

Description

In the Linux kernel, the following vulnerability has been resolved: vsock/virtio: discard packets if the transport changes If the socket has been de-assigned or assigned to another transport, we must discard any packets received because they are not expected and would cause issues when we access vsk->transport. A possible scenario is described by Hyunwoo Kim in the attached link, where after a first connect() interrupted by a signal, and a second connect() failed, we can find `vsk->transport` at NULL, leading to a NULL pointer dereference.

Frequently asked questions

What is CVE-2025-21669?
In the Linux kernel, the following vulnerability has been resolved: vsock/virtio: discard packets if the transport changes If the socket has been de-assigned or assigned to another transport, we must discard any packets received because they are not expected and would cause issues when we access vsk->transport. A possible scenario is described by Hyunwoo Kim in the attached link, where after a first connect() interrupted by a signal, and a second connect() failed, we can find `vsk->transport` at NULL, leading to a NULL pointer dereference.
How severe is CVE-2025-21669?
CVE-2025-21669 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-21669 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (12th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-21669?
CVE-2025-21669 primarily affects Linux Linux Kernel. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-21669?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-21669 have an EU (EUVD) identifier?
Yes. CVE-2025-21669 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-2618.
When was CVE-2025-21669 published?
CVE-2025-21669 was published on 2025-01-31 and last updated on 2026-06-17.

References

Affected products (8)

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