CVE-2024-26704

Advisory lineage Upstream: 0 Downstream: 41
Analyzed
Published: 03 Apr 2024, 14:55
Last modified:11 May 2026, 20:02

Vulnerability Summary

Overall Risk (default)
medium
31/100
CVSS Score
7.8 HIGH
v3.1 (nvd)
EPSS Score
0.01% LOW
0% probability 0.00%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

03 Apr 2024, 14:55
Published
Vulnerability first disclosed
11 May 2026, 20:02
Last Modified
Vulnerability information updated

Description

In the Linux kernel, the following vulnerability has been resolved: ext4: fix double-free of blocks due to wrong extents moved_len In ext4_move_extents(), moved_len is only updated when all moves are successfully executed, and only discards orig_inode and donor_inode preallocations when moved_len is not zero. When the loop fails to exit after successfully moving some extents, moved_len is not updated and remains at 0, so it does not discard the preallocations. If the moved extents overlap with the preallocated extents, the overlapped extents are freed twice in ext4_mb_release_inode_pa() and ext4_process_freed_data() (as described in commit 94d7c16cbbbd ("ext4: Fix double-free of blocks with EXT4_IOC_MOVE_EXT")), and bb_free is incremented twice. Hence when trim is executed, a zero-division bug is triggered in mb_update_avg_fragment_size() because bb_free is not zero and bb_fragments is zero. Therefore, update move_len after each extent move to avoid the issue.

CVSS Metrics

  • v3.1•HIGH•Score: 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS Trends

Current EPSS score: 0.01%• Percentile: 2%

Techniques & Countermeasures

  • CWE-415•Double Free

    The product calls free() twice on the same memory address.

Affected Systems

  • debian•debian_linux

    10.0

  • linux•linux

    ≥ fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a, < b4fbb89d722cbb16beaaea234b7230faaaf68c71 | ≥ fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a, < afbcad9ae7d6d11608399188f03a837451b6b3a1 | ≥ fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a, < d033a555d9a1cf53dbf3301af7199cc4a4c8f537 | ≥ fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a, < afba9d11320dad5ce222ac8964caf64b7b4bedb1 | ≥ fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a, < 185eab30486ba3e7bf8b9c2e049c79a06ffd2bc1 | ≥ fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a, < 2883940b19c38d5884c8626483811acf4d7e148f | ≥ fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a, < 559ddacb90da1d8786dd8ec4fd76bbfa404eaef6 | ≥ fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a, < 55583e899a5357308274601364741a83e78d6ac4 | 3.18

  • linux•linux_kernel

    ≥ 3.18, < 4.19.307 | ≥ 4.20, < 5.4.269 | ≥ 5.5, < 5.10.210 | ≥ 5.11, < 5.15.149 | ≥ 5.16, < 6.1.79 | ≥ 6.2, < 6.6.18 | ≥ 6.7, < 6.7.6 | 6.8:rc1 | 6.8:rc2

References (10)