CVE-2025-21972 — MEDIUM (5.5)

Q: How severe is CVE-2025-21972?

CVE-2025-21972 has been rated MEDIUM with a CVSS base score of 5.5/10. Review the CVSS metrics above for detailed severity breakdown.

Q: Is there a patch for CVE-2025-21972?

Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel.

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: net: mctp: unshare packets when reassembling Ensure that the frag_list used for reassembly isn't shared with other packets. This avoids incorrect reassembly when packets are cloned, and prevents a memory leak due to circular references between fragments and their skb_shared_info. The upcoming MCTP-over-USB driver uses skb_clone which can trigger the problem - other MCTP drivers don't share SKBs. A kunit test is added to reproduce the issue.

CVSS Score

5.5

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Attack Vector

LOCAL

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

NONE

Scope

UNCHANGED

Confidentiality

NONE

Integrity

NONE

Availability

HIGH

Affected Products

Vendor	Product	Versions
Linux	Linux Kernel	>= 5.15, < 6.12.20

Related Weaknesses (CWE)

CWE-401

References

FAQ

What is CVE-2025-21972?

CVE-2025-21972 is a vulnerability with a CVSS score of 5.5 (MEDIUM). In the Linux kernel, the following vulnerability has been resolved: net: mctp: unshare packets when reassembling Ensure that the frag_list used for reassembly isn't shared with other packets. This a...

How severe is CVE-2025-21972?

CVE-2025-21972 has been rated MEDIUM with a CVSS base score of 5.5/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2025-21972?

Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel.