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.
CVE-2025-21972
CVSS base score
8.8 (v3.1)
Severity
HIGH
Attack vector
Adjacent_network
Weakness
CWE-401
Last modified
October 30, 2026
CVSS vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
linux linux kernel
References
- git.kernel.org
- git.kernel.org Patch
- git.kernel.org
- git.kernel.org Patch
- git.kernel.org Patch