CVE-2025-21972

MEDIUMNVD 5.55.5—
EchelonGraph scoreMEDIUM confidence

Score 5.5 from GitHub Security Advisory published 2025-04-01. NVD baseline CVSS 5.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
5.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.5Exploit: None knownExposed: 0

A fix is available — apply it.

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 v3
5.5
EG Score
5.5(medium)
EG Risk
29(Track)
EG Risk 29/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity55% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
14%
KEV
Not listed

Published

April 1, 2025

Last Modified

August 5, 2026

Advisory Details (3)

Auto-updated Aug 2, 2026
No patch confirmed yet.
generic

net: mctp: unshare packets when reassembling - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/f5d83cf0eeb90fade4d5c4d17d24b8bee9ceeecc
generic

net: mctp: unshare packets when reassembling - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/f44fff3d3c6cd67b6f348b821d73c4d6888c7a6e
generic

net: mctp: unshare packets when reassembling - kernel/git/stable/linux.git - Linux kernel stable tree

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

Patch Availability(19)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulinux-tools-oem-24.04b (6.11.0-1024.24) @ noble2026-05-30ubuntu
ubuntulinux-virtual-hwe-24.04-edge (6.11.0-28.28) @ oracular2026-05-30ubuntu
ubuntulinux-tools-lowlatency-hwe-24.04 (6.11.0-1015.16~24.04.2) @ noble2026-05-30ubuntu
ubuntulinux-tools-azure-6.11 (6.11.0-1018.18) @ oracular2026-05-30ubuntu
ubuntulinux-virtual-6.8 (6.8.0-84.84) @ noble2026-05-30ubuntu
ubuntulinux-tools-raspi-6.8 (6.8.0-1039.43) @ noble2026-05-30ubuntu
ubuntulinux-tools-realtime-6.8.1 (6.8.1-1034.35) @ noble2026-05-30ubuntu
ubuntulinux-tools-azure-lts-24.04 (6.8.0-1038.44) @ noble2026-05-30ubuntu
ubuntulinux-tools-realtime-hwe-22.04 (6.8.1-1034.35~22.04.1) @ jammy2026-05-30ubuntu
ubuntulinux-virtual-hwe-22.04-edge (6.8.0-84.84~22.04.1) @ jammy2026-05-30ubuntu
ubuntulinux-tools-ibm-lts-24.04 (6.8.0-1037.37) @ noble2026-05-30ubuntu
ubuntulinux-tools-nvidia-lowlatency-64k-6.8 (6.8.0-1039.42.1) @ noble2026-05-30ubuntu
ubuntulinux-tools-gcp-edge (6.8.0-1040.42~22.04.1) @ jammy2026-05-30ubuntu
ubuntulinux-tools-raspi-realtime-6.8 (6.8.0-2031.32) @ noble2026-05-30ubuntu
ubuntulinux-virtual-hwe-22.04-edge (6.8.0-85.85~22.04.1) @ jammy2026-05-30ubuntu
ubuntulinux-tools-oracle-lts-24.04 (6.8.0-1037.38) @ noble2026-05-30ubuntu
ubuntulinux-tools-azure-nvidia-lts-24.04 (6.8.0-1025.27) @ noble2026-05-30ubuntu
ubuntulinux-tools-oracle-edge (6.8.0-1037.38~22.04.1) @ jammy2026-05-30ubuntu
linuxKernel @ 6.12.20—osv

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(3 across 3 ecosystems)
Debian:12(1)
PackageVulnerable rangeFixed inDependents
linux6.1.106-1 ... 7.2~rc7-1~exp1 (350 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
linux—6.12.20-1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
linux—6.12.20-1—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

All Vendor Advisories

(19)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 5× in last 7d / 26× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 153 total refreshes for this CVE.

  1. 2026-09-20 20:15 UTCEPSS rescore
  2. 2026-09-18 19:27 UTCEPSS rescore
  3. 2026-09-16 14:06 UTCEPSS rescore
  4. 2026-09-16 05:13 UTCEPSS rescore
  5. 2026-09-15 03:09 UTCEPSS rescore
  6. 2026-09-13 16:46 UTCEPSS rescore
  7. 2026-09-12 15:00 UTCEPSS rescore
  8. 2026-09-11 14:51 UTCEPSS rescore
  9. 2026-09-11 09:35 UTCEPSS rescore
  10. 2026-09-10 09:33 UTCEPSS rescore
  11. 2026-09-08 21:59 UTCEPSS rescore
  12. 2026-09-07 16:00 UTCEPSS rescore
  13. 2026-09-07 12:48 UTCOSV refresh
  14. 2026-09-06 13:46 UTCEPSS rescore
  15. 2026-09-06 13:46 UTCEPSS rescore
  16. 2026-09-05 15:28 UTCEPSS rescore
  17. 2026-09-02 14:11 UTCEPSS rescore
  18. 2026-09-01 13:52 UTCEPSS rescore
  19. 2026-09-01 04:38 UTCEPSS rescore
  20. 2026-08-30 19:16 UTCEPSS rescore
  21. 2026-08-30 01:21 UTCEPSS rescore
  22. 2026-08-28 21:40 UTCEPSS rescore
  23. 2026-08-27 14:24 UTCEPSS rescore
  24. 2026-08-25 13:47 UTCEPSS rescore
  25. 2026-08-23 00:18 UTCEPSS rescore
Show 75 more
  1. 2026-08-21 23:48 UTCEPSS rescore
  2. 2026-08-20 22:31 UTCOSV refresh
  3. 2026-08-19 17:03 UTCEPSS rescore
  4. 2026-08-18 13:47 UTCEPSS rescore
  5. 2026-08-17 13:46 UTCEPSS rescore
  6. 2026-08-16 14:55 UTCEPSS rescore
  7. 2026-08-16 02:13 UTCEPSS rescore
  8. 2026-08-16 02:13 UTCEPSS rescore
  9. 2026-08-15 01:29 UTCEPSS rescore
  10. 2026-08-13 21:59 UTCEPSS rescore
  11. 2026-08-12 13:50 UTCEPSS rescore
  12. 2026-08-10 23:59 UTCEPSS rescore
  13. 2026-08-09 13:45 UTCEPSS rescore
  14. 2026-08-07 16:26 UTCEPSS rescore
  15. 2026-08-06 13:46 UTCEPSS rescore
  16. 2026-08-05 19:16 UTCEPSS rescore
  17. 2026-08-05 14:00 UTCEG score recompute
  18. 2026-08-05 14:00 UTCVendor advisory
  19. 2026-08-05 14:00 UTCGHSA enrichment
  20. 2026-08-04 15:09 UTCEPSS rescore
  21. 2026-08-04 10:37 UTCEPSS rescore
  22. 2026-08-03 10:35 UTCEPSS rescore
  23. 2026-08-02 02:25 UTCEPSS rescore
  24. 2026-08-01 04:15 UTCEPSS rescore
  25. 2026-07-30 16:27 UTCEPSS rescore
  26. 2026-07-30 07:16 UTCEG score recompute
  27. 2026-07-30 07:16 UTCVendor advisory
  28. 2026-07-30 07:15 UTCGHSA enrichment
  29. 2026-07-30 01:29 UTCEPSS rescore
  30. 2026-07-28 15:35 UTCEPSS rescore
  31. 2026-07-27 14:12 UTCEPSS rescore
  32. 2026-07-26 14:53 UTCEPSS rescore
  33. 2026-07-25 14:17 UTCEPSS rescore
  34. 2026-07-24 14:17 UTCEPSS rescore
  35. 2026-07-24 10:11 UTCOSV refresh
  36. 2026-07-23 14:17 UTCEPSS rescore
  37. 2026-07-23 02:50 UTCEG score recompute
  38. 2026-07-22 14:07 UTCEPSS rescore
  39. 2026-07-22 14:07 UTCEPSS rescore
  40. 2026-07-21 15:24 UTCEPSS rescore
  41. 2026-07-20 17:07 UTCEPSS rescore
  42. 2026-07-19 14:30 UTCEPSS rescore
  43. 2026-07-19 14:30 UTCEPSS rescore
  44. 2026-07-19 02:28 UTCEPSS rescore
  45. 2026-07-19 02:28 UTCEPSS rescore
  46. 2026-07-18 10:03 UTCEPSS rescore
  47. 2026-07-16 17:02 UTCEPSS rescore
  48. 2026-07-15 16:57 UTCEPSS rescore
  49. 2026-07-15 16:57 UTCEPSS rescore
  50. 2026-07-15 01:59 UTCEPSS rescore
  51. 2026-07-13 22:29 UTCEPSS rescore
  52. 2026-07-13 22:29 UTCEPSS rescore
  53. 2026-07-13 06:12 UTCEPSS rescore
  54. 2026-07-13 06:12 UTCEPSS rescore
  55. 2026-07-12 05:46 UTCEPSS rescore
  56. 2026-07-12 05:46 UTCEPSS rescore
  57. 2026-07-11 08:27 UTCEPSS rescore
  58. 2026-07-11 08:26 UTCEPSS rescore
  59. 2026-07-09 19:09 UTCEPSS rescore
  60. 2026-07-08 15:14 UTCEPSS rescore
  61. 2026-07-07 13:45 UTCEPSS rescore
  62. 2026-07-07 05:51 UTCOSV refresh
  63. 2026-07-06 16:26 UTCEPSS rescore
  64. 2026-07-06 02:22 UTCEPSS rescore
  65. 2026-07-06 02:22 UTCEPSS rescore
  66. 2026-07-05 02:30 UTCEPSS rescore
  67. 2026-07-04 06:30 UTCEPSS rescore
  68. 2026-07-01 15:06 UTCEPSS rescore
  69. 2026-06-30 23:21 UTCEPSS rescore
  70. 2026-06-30 23:21 UTCEPSS rescore
  71. 2026-06-29 14:06 UTCEPSS rescore
  72. 2026-06-28 14:07 UTCEPSS rescore
  73. 2026-06-28 14:07 UTCEPSS rescore
  74. 2026-06-28 04:55 UTCEPSS rescore
  75. 2026-06-28 04:55 UTCEPSS rescore

Related CVEs(same product + same vendor + same CWE)

Frequently asked(5)

What is CVE-2025-21972?
CVE-2025-21972 is a medium vulnerability published on April 1, 2025. 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…
When was CVE-2025-21972 disclosed?
CVE-2025-21972 was first published in the National Vulnerability Database on April 1, 2025, with the most recent update on August 5, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2025-21972 actively exploited?
CVE-2025-21972 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 86.0% of all scored CVEs.
What is the CVSS score of CVE-2025-21972?
CVE-2025-21972 has a CVSS v3 base score of 5.5 (NVD).
How do I remediate CVE-2025-21972?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2025-21972, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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