CVE-2026-89961powerpc/mm: fix wrong addr_pfn tracking in compound vmemmap population
- 7.8HighCVSS base score
- 0.18%Exploitation in 30 daysEPSS · top 93% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
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.
Timeline
ID reserved
By Linux
- 5 days later
· 5 days later
Published
- 33 days later
· 33 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Received | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.18% · top 93% of all CVEs (14 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.8.
Affected products
- affected f2b79c0d79683d552369bb9a7282c1f0226fc566 – < b96be860673f9fbbf12cdadb0b25fc4d6d4d207f
- affected f2b79c0d79683d552369bb9a7282c1f0226fc566 – < e163c7184acf36ac20a248498f4a16016057ca01
- affected f2b79c0d79683d552369bb9a7282c1f0226fc566 – < 9c914b7a0bd18834505c65f22225ce22c152b2d9
- affected f2b79c0d79683d552369bb9a7282c1f0226fc566 – < 7968852a7ca3ce81477ec5b4494a28d612f35a97
- affected f2b79c0d79683d552369bb9a7282c1f0226fc566 – < 89a4ae32764172468dea303eb6ae90fe6c859712
- affected 6.6
- unaffected < 6.6
- unaffected 6.6.157 – ≤ 6.6.*
- unaffected 6.12.110 – ≤ 6.12.*
- unaffected 6.18.51 – ≤ 6.18.*
- unaffected 7.2.5 – ≤ 7.2.*
- unaffected 7.3 – ≤ *
References
References5
- https://git.kernel.org/stable/c/b96be860673f9fbbf12cdadb0b25fc4d6d4d207f (opens in a new tab)
- https://git.kernel.org/stable/c/e163c7184acf36ac20a248498f4a16016057ca01 (opens in a new tab)
- https://git.kernel.org/stable/c/9c914b7a0bd18834505c65f22225ce22c152b2d9 (opens in a new tab)
- https://git.kernel.org/stable/c/7968852a7ca3ce81477ec5b4494a28d612f35a97 (opens in a new tab)
- https://git.kernel.org/stable/c/89a4ae32764172468dea303eb6ae90fe6c859712 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-80561 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-89961)Record last updated .