CVE-2026-45991

HIGHPre-NVD 7.87.8—
EchelonGraph scoreMEDIUM confidence

Score 7.8 from GitHub Security Advisory (severity: HIGH) published 2026-05-27. the CNA's CVSS baseline 7.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cna:linux, epss, ghsa
Trending — 5 sources updated this week
7.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.8Exploit: None knownExposed: 0

A fix is available — apply it.

In the Linux kernel, the following vulnerability has been resolved:

udf: fix partition descriptor append bookkeeping

Mounting a crafted UDF image with repeated partition descriptors can trigger a heap out-of-bounds write in part_descs_loc[].

handle_partition_descriptor() deduplicates entries by partition number, but appended slots never record partnum. As a result duplicate Partition Descriptors are appended repeatedly and num_part_descs keeps growing.

Once the table is full, the growth path still sizes the allocation from partnum even though inserts are indexed by num_part_descs. If partnum is already aligned to PART_DESC_ALLOC_STEP, ALIGN(partnum, step) can keep the old capacity and the next append writes past the end of the table.

Store partnum in the appended slot and size growth from the next append count so deduplication and capacity tracking follow the same model.

CVSS v3
7.8
EG Score
7.8(medium)
EG Risk
40(Track)
EG Risk 40/100SSVC: 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
Severity78% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
7%
KEV
Not listed

Published

May 27, 2026

Last Modified

August 5, 2026

Advisory Details (4)

Auto-updated Jun 3, 2026
No patch confirmed yet.
generic

udf: fix partition descriptor append bookkeeping - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/b5597bb83fc37b5b5da74a4453fa920b932cf39a
generic

udf: fix partition descriptor append bookkeeping - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/08fa5d818e5bf53c7ca234d88ba334f32004e9b6
generic

udf: fix partition descriptor append bookkeeping - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/08841b06fa64d8edbd1a21ca6e613420c90cc4b8
generic

udf: fix partition descriptor append bookkeeping - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/058b451b1039f056d1362c4fec2229e522366ab0

Vendor Advisories for CVE-2026-45991(6)

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

Patch Availability(25)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulinux-tools-oem-7.0 (7.0.0-1008.8) @ resolute2026-09-14ubuntu
ubuntulinux-tools-raspi-realtime-7.0 (7.0.0-1014.14) @ resolute2026-09-14ubuntu
ubuntulinux-tools-nvidia-hwe-24.04-edge (7.0.0-1013.13) @ resolute2026-09-14ubuntu
ubuntulinux-virtual-6.8 (6.8.0-136.136) @ noble2026-09-14ubuntu
ubuntulinux-virtual-hwe-24.04-edge (7.0.0-28.28~24.04.1) @ noble2026-09-14ubuntu
ubuntulinux-tools-gcp-fips-6.8 (6.8.0-1064.72+fips1) @ noble2026-09-14ubuntu
ubuntulinux-tools-oracle-lts-24.04 (6.8.0-1058.61) @ noble2026-09-14ubuntu
ubuntulinux-tools-oracle-edge (6.8.0-1058.61~22.04.1) @ jammy2026-09-14ubuntu
ubuntulinux-tools-nvidia-lowlatency-64k-6.8 (6.8.0-1059.62.1) @ noble2026-09-14ubuntu
ubuntulinux-tools-azure-fde-7.0 (7.0.0-1009.9) @ resolute2026-09-14ubuntu
ubuntulinux-tools-aws-lts-24.04 (6.8.0-1061.64+1) @ noble2026-09-14ubuntu
ubuntulinux-tools-azure-lts-24.04 (6.8.0-1063.71) @ noble2026-09-14ubuntu
ubuntulinux-tools-azure-fde-lts-24.04 (6.8.0-1062.69) @ noble2026-09-14ubuntu
ubuntulinux-tools-azure-fips-6.8 (6.8.0-1063.71+fips2) @ noble2026-09-14ubuntu
ubuntulinux-tools-azure-fde-6.8 (6.8.0-1062.69~22.04.1) @ jammy2026-09-14ubuntu
ubuntulinux-tools-aws-fips-6.8 (6.8.0-1061.64+fips1) @ noble2026-09-14ubuntu
ubuntulinux-tools-ibm-edge (6.8.0-1061.62~22.04.1) @ jammy2026-09-14ubuntu
ubuntulinux-virtual-hwe-22.04-edge (6.8.0-136.136~22.04.1) @ jammy2026-09-14ubuntu
ubuntulinux-virtual-hwe-26.04-edge (7.0.0-27.27) @ resolute2026-09-14ubuntu
ubuntulinux-tools-raspi-realtime-6.8 (6.8.0-2050.52) @ noble2026-09-14ubuntu
redhatkernel-0:5.14.0-687.41.1.el9_82026-08-20redhat
redhatkernel-0:6.12.0-211.49.1.el10_22026-08-20redhat
redhatkernel-rt-0:4.18.0-553.155.1.rt7.496.el8_102026-08-12redhat
redhatkernel-0:4.18.0-553.155.1.el8_102026-08-12redhat
linuxKernel @ 5.10.259—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

(5 across 4 ecosystems)
Debian:11(2)
PackageVulnerable rangeFixed inDependents
linux5.10.103-1 ... 5.10.92-2 (54 versions)5.10.259-1—
linux-6.16.1.106-3~deb11u1 ... 6.1.174-1~deb11u1 (20 versions)6.1.176-1~deb11u1—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
linux6.1.106-1 ... 6.1.99-1 (53 versions)6.1.176-1—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
linux6.12.38-1 ... 6.12.88-1~bpo12+1 (21 versions)6.12.88-1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
linux6.12.100-1 ... 7.0.4-1~bpo13+1 (134 versions)7.0.4-1—

Weakness Classification(1)

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

Additional Vendor Advisories

(20)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 10× in last 7d / 42× 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 294 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-45991?
CVE-2026-45991 is a high vulnerability published on May 27, 2026. In the Linux kernel, the following vulnerability has been resolved: udf: fix partition descriptor append bookkeeping Mounting a crafted UDF image with repeated partition descriptors can trigger a heap out-of-bounds write in partdescsloc[]. handlepartitiondescriptor() deduplicates entries by…
When was CVE-2026-45991 disclosed?
CVE-2026-45991 was first published in the National Vulnerability Database on May 27, 2026, 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-2026-45991 actively exploited?
CVE-2026-45991 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 93.4% of all scored CVEs.
What is the CVSS score of CVE-2026-45991?
CVE-2026-45991 has a CVSS v4.0 base score of 7.8 (CNA self-assessment; NVD's own analysis pending).
How do I remediate CVE-2026-45991?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-45991, 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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