Vulnerability in Linux
CVE-2025-21972
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.002 (12.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 12th percentile — 12.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000
Affected products
- Linux — versions 4a992bbd365094730a31bae1e12a6ca695336d57, 5.15, 0
- Linux Kernel — versions 6.14
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2025-21972?
- CVE-2025-21972 is a high-severity vulnerability in Linux, classified under Missing Release of Memory after Effective Lifetime. CVSS score: 8.8/10. Published 2025-04-01.
- How severe is CVE-2025-21972?
- High severity. CVSS v3 base score is 8.8 out of 10.