CVE-2026-89961

HIGHPre-NVD 7.87.8—
EchelonGraph scoreHIGH confidence

Score 7.8 from GitHub Security Advisory (severity: HIGH) published 2026-09-16. A secondary CVSS source baseline 7.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
7.8EG
EchelonGraph verdictPlan mitigationSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.2%CVSS: 7.8Exploit: None knownExposed services: Not assessed

No fix is confirmed yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for the fix.

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

powerpc/mm: fix wrong addr_pfn tracking in compound vmemmap population

vmemmap_populate_compound_pages() uses addr_pfn to determine the PFN offset within a compound page and to decide whether the current vmemmap slot should be populated as a head page mapping or should reuse a tail page mapping.

However, addr_pfn is advanced manually in parallel with addr. The loop itself progresses in vmemmap address space, so each PAGE_SIZE step in addr covers PAGE_SIZE / sizeof(struct page) struct page slots. Since addr_pfn is compared against nr_pages in data-PFN units, it should advance by the same number of PFNs. The existing manual increments do not match that and therefore do not reliably track the PFN corresponding to the current addr.

As a result, pfn_offset can be computed from the wrong PFN and the code can make the head/tail decision for the wrong compound-page position.

Fix this by deriving addr_pfn directly from the current vmemmap address instead of carrying it as loop state.

CVSS v3
7.8
EG Score
7.8HIGHhigh confidence
EG Risk
40
EG Risk 40/100CISA SSVC

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%
CISA SSVC: Track at low or medium mission impact; Track or Attend at high (mission-essential systems).
Action: No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines at low or medium mission impact and sooner than that at high, and watch the vendor's advisory for the fix.
EPSS PROB
0.2%
EPSS %ILE
6th
KEV
Not listed

CISA SSVCTrack at low or medium mission impact; Track or Attend at high (mission-essential systems).

No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines at low or medium mission impact and sooner than that at high, and watch the vendor's advisory for the fix.

Exploitation none (no KEV listing, exploit record or EPSS ≥ 50%) · Automatable unknown (not published for this CVE) · Technical impact partial (CVSS below 9.0). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table

Published

September 16, 2026

Last Modified

September 16, 2026

Advisory Details (5)

Auto-updated Sep 16, 2026
No patch confirmed yet.
generic

powerpc/mm: fix wrong addr_pfn tracking in compound vmemmap population - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/e163c7184acf36ac20a248498f4a16016057ca01
generic

powerpc/mm: fix wrong addr_pfn tracking in compound vmemmap population - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/b96be860673f9fbbf12cdadb0b25fc4d6d4d207f
generic

powerpc/mm: fix wrong addr_pfn tracking in compound vmemmap population - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/9c914b7a0bd18834505c65f22225ce22c152b2d9
generic

powerpc/mm: fix wrong addr_pfn tracking in compound vmemmap population - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/89a4ae32764172468dea303eb6ae90fe6c859712
generic

powerpc/mm: fix wrong addr_pfn tracking in compound vmemmap population - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/7968852a7ca3ce81477ec5b4494a28d612f35a97

Vendor Advisories for CVE-2026-89961(2)

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

Affected Packages

(3 across 3 ecosystems)
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
linux-6.126.12.100-1~deb12u1, 6.12.101-1~deb12u1, 6.12.107-1~deb12u1
  • every version up to 6.12.111-1~deb12u1: fixed in 6.12.111-1~deb12u1
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
linux6.12.100-1 ... 6.12.96-1 (35 versions)
  • every version up to 6.12.111-1: fixed in 6.12.111-1
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
linux6.12.100-1 ... 7.2~rc7-1~exp1 (179 versions)
  • every version up to 7.2.6-1: fixed in 7.2.6-1
—

Data Freshness Timeline

(refreshed 39× in last 7d / 113× 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 113 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-89961?
CVE-2026-89961 is a high vulnerability published on September 16, 2026. In the Linux kernel, the following vulnerability has been resolved: powerpc/mm: fix wrong addr_pfn tracking in compound vmemmap population vmemmappopulatecompoundpages() uses addrpfn to determine the PFN offset within a compound page and to decide whether the current vmemmap slot should be…
When was CVE-2026-89961 disclosed?
CVE-2026-89961 was first published on September 16, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-89961 actively exploited?
CVE-2026-89961 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.2% probability of exploitation in the next 30 days (6th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-89961?
CVE-2026-89961 has a CVSS base score of 7.8 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-89961?
No fix for CVE-2026-89961 is confirmed yet. Until one is published, restrict network exposure of the affected system or apply the vendor's mitigation — for example, keep it off the internet or limit it to trusted networks — and watch the vendor's advisory for the fix. The vendor advisories EchelonGraph has for CVE-2026-89961 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-89961

Explore →

Is Your Infrastructure Affected by CVE-2026-89961?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Book a Demo →Browse All CVEs