CVE-2026-31449 (GCVE-0-2026-31449)

Vulnerability from cvelistv5 – Published: 2026-04-22 13:53 – Updated: 2026-04-23 15:18
VLAI?
Title
ext4: validate p_idx bounds in ext4_ext_correct_indexes
Summary
In the Linux kernel, the following vulnerability has been resolved: ext4: validate p_idx bounds in ext4_ext_correct_indexes ext4_ext_correct_indexes() walks up the extent tree correcting index entries when the first extent in a leaf is modified. Before accessing path[k].p_idx->ei_block, there is no validation that p_idx falls within the valid range of index entries for that level. If the on-disk extent header contains a corrupted or crafted eh_entries value, p_idx can point past the end of the allocated buffer, causing a slab-out-of-bounds read. Fix this by validating path[k].p_idx against EXT_LAST_INDEX() at both access sites: before the while loop and inside it. Return -EFSCORRUPTED if the index pointer is out of range, consistent with how other bounds violations are handled in the ext4 extent tree code.
Severity ?
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: a86c61812637c7dd0c57e29880cffd477b62f2e7 , < 407c944f217c17d4343148011acafebc604d55e1 (git)
Affected: a86c61812637c7dd0c57e29880cffd477b62f2e7 , < 93f2e975ed658ce09db4d4c2877ca2c06540df83 (git)
Affected: a86c61812637c7dd0c57e29880cffd477b62f2e7 , < 01bf1e0b997d82c0e353b51ed74ef99698043c33 (git)
Affected: a86c61812637c7dd0c57e29880cffd477b62f2e7 , < 2acb5c12ebd860f30e4faf67e6cc8c44ddfe5fe8 (git)
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    Linux Linux Affected: 2.6.19
Unaffected: 0 , < 2.6.19 (semver)
Unaffected: 6.12.80 , ≤ 6.12.* (semver)
Unaffected: 6.18.21 , ≤ 6.18.* (semver)
Unaffected: 6.19.11 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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  • 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.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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