CVE-2026-31694 (GCVE-0-2026-31694)

Vulnerability from cvelistv5 – Published: 2026-05-01 13:53 – Updated: 2026-05-03 05:45
VLAI?
Title
fuse: reject oversized dirents in page cache
Summary
In the Linux kernel, the following vulnerability has been resolved: fuse: reject oversized dirents in page cache fuse_add_dirent_to_cache() computes a serialized dirent size from the server-controlled namelen field and copies the dirent into a single page-cache page. The existing logic only checks whether the dirent fits in the remaining space of the current page and advances to a fresh page if not. It never checks whether the dirent itself exceeds PAGE_SIZE. As a result, a malicious FUSE server can return a dirent with namelen=4095, producing a serialized record size of 4120 bytes. On 4 KiB page systems this causes memcpy() to overflow the cache page by 24 bytes into the following kernel page. Reject dirents that cannot fit in a single page before copying them into the readdir cache.
Severity ?
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 69e34551152a286f827d54dcb5700da6aeaac1fb , < d23ad78bfd205eac26766e38ba7d79f279131098 (git)
Affected: 69e34551152a286f827d54dcb5700da6aeaac1fb , < 45c05af36311624c1148123caeb011312495d86b (git)
Affected: 69e34551152a286f827d54dcb5700da6aeaac1fb , < 7de93abfaae1b2dc94da8a07a36421bd073f1d8f (git)
Affected: 69e34551152a286f827d54dcb5700da6aeaac1fb , < 474ce83c96a55f2eeb14dee2be375eeadfdacdf5 (git)
Affected: 69e34551152a286f827d54dcb5700da6aeaac1fb , < 51a8de6c50bf947c8f534cd73da4c8f0a13e7bed (git)
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    Linux Linux Affected: 4.20
Unaffected: 0 , < 4.20 (semver)
Unaffected: 6.6.136 , ≤ 6.6.* (semver)
Unaffected: 6.12.84 , ≤ 6.12.* (semver)
Unaffected: 6.18.25 , ≤ 6.18.* (semver)
Unaffected: 7.0.2 , ≤ 7.0.* (semver)
Unaffected: 7.1-rc1 , ≤ * (original_commit_for_fix)
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{
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    "dateReserved": "2026-03-09T15:48:24.131Z",
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  }
}


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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.