CVE-2025-21972
Medium
Elevated severity or exploit probability.
CVSS base
8.8
HIGH
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS — probability of exploitation (30 days)
0.2%
14.0th percentile
CISA KEV
Not listed
Weakness / dates
CWE-401
Published 2025-04-01 · modified 2026-07-30
CVSS breakdown
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
| Attack Vector | A | Adjacent |
| Attack Complexity | L | Low |
| Privileges Required | N | None |
| User Interaction | N | None |
| Scope | U | Unchanged |
| Confidentiality | H | High |
| Integrity | H | High |
| Availability | H | High |
Timeline
- 2025-04-01 — Published (NVD)
- 2026-07-30 — Last modified (NVD)
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.