CVE-2025-21972

medium

In the Linux kernel, the following vulnerability has been resolved: net: mctp: unshare packets when reassembling Ensure that the frag_list used for reassembl…

Vendor / product: Linux — linux kernel

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

5.5

5.5 (CVSS v3.1)

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

Severity source: NVD CVSS v3.1 (nvd@nist.gov)

Timeline (UTC)

Published: 2025-04-01 16:15

Modified: 2026-10-30 13:17

NVD status: Modified

Last synced 3 days ago

Verified against the source API 2026-10-30 13:38 UTC

Exploitation

Not listed in CISA KEV (as of last catalog sync)

Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).

Affected products

linux / linux_kernel ≥5.15 <6.12.20, ≥6.13 <6.13.8, 6.14

Weakness classification (CWE)

CWE-401

Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.

Mitigation & advisories

Patch / mitigation: https://git.kernel.org/stable/c/5c47d5bfa7b096cf8890afac32141c578583f8e0

Patch / mitigation: https://git.kernel.org/stable/c/f44fff3d3c6cd67b6f348b821d73c4d6888c7a6e

Patch / mitigation: https://git.kernel.org/stable/c/f5d83cf0eeb90fade4d5c4d17d24b8bee9ceeecc

References

https://git.kernel.org/stable/c/3d0281d0713952e8dd14d6d47e3a9c345c28a3b7 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/5c47d5bfa7b096cf8890afac32141c578583f8e0 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/771087069a27c35c0a9fd7cc74fe7725b189b96b 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/f44fff3d3c6cd67b6f348b821d73c4d6888c7a6e 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/f5d83cf0eeb90fade4d5c4d17d24b8bee9ceeecc 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Data sources

NVD CVE API 2.0 — fetched 2026-10-30 13:38 UTC · record ↗

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CVE-2025-21972

Affected products

Weakness classification (CWE)

Mitigation & advisories

References

Data sources

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