CVE-2026-31420

MEDIUMNVD 5.55.5
EchelonGraph scoreMEDIUM confidence

Score 5.5 from GitHub Security Advisory published 2026-04-13. NVD baseline CVSS 5.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Trending — 4 sources updated this week
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:

bridge: mrp: reject zero test interval to avoid OOM panic

br_mrp_start_test() and br_mrp_start_in_test() accept the user-supplied interval value from netlink without validation. When interval is 0, usecs_to_jiffies(0) yields 0, causing the delayed work (br_mrp_test_work_expired / br_mrp_in_test_work_expired) to reschedule itself with zero delay. This creates a tight loop on system_percpu_wq that allocates and transmits MRP test frames at maximum rate, exhausting all system memory and causing a kernel panic via OOM deadlock.

The same zero-interval issue applies to br_mrp_start_in_test_parse() for interconnect test frames.

Use NLA_POLICY_MIN(NLA_U32, 1) in the nla_policy tables for both IFLA_BRIDGE_MRP_START_TEST_INTERVAL and IFLA_BRIDGE_MRP_START_IN_TEST_INTERVAL, so zero is rejected at the netlink attribute parsing layer before the value ever reaches the workqueue scheduling code. This is consistent with how other bridge subsystems (br_fdb, br_mst) enforce range constraints on netlink attributes.

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
1%
KEV
Not listed

Published

April 13, 2026

Last Modified

September 14, 2026

Advisory Details (4)

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

bridge: mrp: reject zero test interval to avoid OOM panic - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/fa6e24963342de4370e3a3c9af41e38277b74cf3
generic

bridge: mrp: reject zero test interval to avoid OOM panic - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/e8ec80430bfa520e7352155d6ac632e527cba7aa
generic

bridge: mrp: reject zero test interval to avoid OOM panic - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/c9bc352f716d1bebfe43354bce539ec2d0223b30
generic

bridge: mrp: reject zero test interval to avoid OOM panic - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/630a15a31c2034b5b697f4aabc769b9d80d82446

Vendor Advisories for CVE-2026-31420(2)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(2)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulinux-virtual-6.8 (6.8.0-139.139) @ noble2026-09-14ubuntu
linuxKernel @ 6.12.92osv

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

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
linux5.10.103-1 ... 7.2~rc5-1~exp1 (496 versions)
Debian:12(1)
PackageVulnerable rangeFixed inDependents
linux6.1.106-1 ... 7.2~rc7-1~exp1 (350 versions)
Debian:13(1)
PackageVulnerable rangeFixed inDependents
linux6.12.38-1 ... 6.12.94-1~bpo12+1 (27 versions)6.12.94-1
Debian:14(1)
PackageVulnerable rangeFixed inDependents
linux6.12.100-1 ... 6.19~rc8-1~exp1 (125 versions)6.19.12-1

Weakness Classification(1)

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

All Vendor Advisories

(1)

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 9× in last 7d / 23× 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 156 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-31420?
CVE-2026-31420 is a medium vulnerability published on April 13, 2026. In the Linux kernel, the following vulnerability has been resolved: bridge: mrp: reject zero test interval to avoid OOM panic brmrpstarttest() and brmrpstartin_test() accept the user-supplied interval value from netlink without validation. When interval is 0, usecstojiffies(0) yields 0, causing the…
When was CVE-2026-31420 disclosed?
CVE-2026-31420 was first published in the National Vulnerability Database on April 13, 2026, with the most recent update on September 14, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-31420 actively exploited?
CVE-2026-31420 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 99.5% of all scored CVEs.
What is the CVSS score of CVE-2026-31420?
CVE-2026-31420 has a CVSS v3 base score of 5.5 (NVD).
How do I remediate CVE-2026-31420?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-31420, 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

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-31420

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