CVE-2026-31589: Linux kernel · mm: call ->free_folio() directly in folio_unmap_invalidate()
Source GCVE Database
Not known to be exploited · CVSS 9.8 Critical.
Data as of 27 Oct 2026, 00:07 UTC
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 24 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
Description
In the Linux kernel, the following vulnerability has been resolved: mm: call ->free_folio() directly in folio_unmap_invalidate() We can only call filemap_free_folio() if we have a reference to (or hold a lock on) the mapping. Otherwise, we've already removed the folio from the mapping so it no longer pins the mapping and the mapping can be removed, causing a use-after-free when accessing mapping->a_ops. Follow the same pattern as __remove_mapping() and load the free_folio function pointer before dropping the lock on the mapping. That lets us make filemap_free_folio() static as this was the only caller outside filemap.c.
References
- nvd.nist.gov/vuln/detail/CVE-2026-31589 (opens in a new tab)
- git.kernel.org/stable/c/615d9bb2ccad42f9e21d837431e401db2e471195 (opens in a new tab)
- git.kernel.org/stable/c/b667df39d98a7a24be7c2a40ff0863dac1ad2cd7 (opens in a new tab)
- git.kernel.org/stable/c/c330e65ea59c4805d6ab6757c4ddfe8c63acef31 (opens in a new tab)
- git.kernel.org/stable/c/efc52947247a21bbf79059539bbbd40f4ea76f00 (opens in a new tab)