Microsoft advisory for CVE-2026-31449 — azl3 kernel
🔗 CVE IDs covered (1)
📋 Microsoft's advisory
EchelonGraph does not copy Microsoft's advisory page: its FAQ and remediation text are not shown here. Read the advisory on https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-31449. This page also shows what EchelonGraph holds for CVE-2026-31449, with the description from its CVE record, which the CVE Numbering Authority that assigned the CVE wrote: for a CVE Microsoft assigned, often in the words of Microsoft's own advisory.
🎯 Affected products6
- azl3 kernel 6.6.130.1-3 on Azure Linux 3.0
- azl3 kernel 6.6.134.1-2 on Azure Linux 3.0
- azl3 kernel 6.6.137.1-2 on Azure Linux 3.0
- azl3 kernel 6.6.138.1-1 on Azure Linux 3.0
- azl3 kernel 6.6.139.1-1 on Azure Linux 3.0
- azl3 kernel 6.6.141.1-1 on Azure Linux 3.0
🧭 EchelonGraph on CVE-2026-31449
- EchelonGraph score
- 7.8 HIGH
- CISA KEV
- Not listed
- Fix status
- A fix is available — apply it.
Description from the CVE record (CVE.org), as published by its numbering authority
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.
Published by kernel.org, the CVE Numbering Authority that assigned CVE-2026-31449, in its CVE record at CVE.org; reused under the CVE Program's Terms of Use (its licence and MITRE's copyright notice are in our Terms of Service).