CVE-2024-26773: Linux kernel · ext4: avoid allocating blocks from corrupted group in ext4_mb_try_best_found()
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in 5.4.0-1126.136~18.04.1 : patch Linux kernel soon.
Data as of 28 Oct 2026, 10:59 UTC
- Patch
- Available – fixed in 5.4.0-1126.136~18.04.1, 5.4.0-1131.138~18.04.1, 5.4.0-1130.139~18.04.1 +56
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 3 Apr 2024
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.
What to do
Upgrade to a fixed release listed under Affected software.
Patches and advisories
- ubuntu.com/security/notices/USN-6820-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-6821-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-6821-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-6828-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-6820-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-6821-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-6831-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-6821-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-6867-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-6871-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-6892-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-6919-1 (opens in a new tab)
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu Pro Realtime 24.04 LTSlinux-raspi-realtimepkg:deb/ubuntu/linux-raspi-realtime?arch=source&distro=realtime/nobleOther threats | Affected
| Fixed in
|
Ubuntu 22.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=jammyOther threats | Affected
| Fixed in
|
Ubuntu 22.04 LTSlinux-allwinner-5.19pkg:deb/ubuntu/linux-allwinner-5.19?arch=source&distro=jammyOther threats | Affected
| Fixed in– |
Ubuntu 22.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=jammyOther threats | Affected
| Fixed in
|
Ubuntu 22.04 LTSlinux-aws-5.19pkg:deb/ubuntu/linux-aws-5.19?arch=source&distro=jammyOther threats | Affected
| Fixed in– |
Ubuntu 22.04 LTSlinux-aws-6.2pkg:deb/ubuntu/linux-aws-6.2?arch=source&distro=jammyOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
In the Linux kernel, the following vulnerability has been resolved: ext4: avoid allocating blocks from corrupted group in ext4_mb_try_best_found() Determine if the group block bitmap is corrupted before using ac_b_ex in ext4_mb_try_best_found() to avoid allocating blocks from a group with a corrupted block bitmap in the following concurrency and making the situation worse. ext4_mb_regular_allocator ext4_lock_group(sb, group) ext4_mb_good_group // check if the group bbitmap is corrupted ext4_mb_complex_scan_group // Scan group gets ac_b_ex but doesn't use it ext4_unlock_group(sb, group) ext4_mark_group_bitmap_corrupted(group) // The block bitmap was corrupted during // the group unlock gap. ext4_mb_try_best_found ext4_lock_group(ac->ac_sb, group) ext4_mb_use_best_found mb_mark_used // Allocating blocks in block bitmap corrupted group
References
- ubuntu.com/security/CVE-2024-26773 (opens in a new tab)
- git.kernel.org/linus/4530b3660d396a646aad91a787b6ab37cf604b53 (opens in a new tab)
- git.kernel.org/stable/c/21f8cfe79f776287459343e9cfa6055af61328ea (opens in a new tab)
- git.kernel.org/stable/c/260fc96283c0f594de18a1b045faf6d8fb42874d (opens in a new tab)
- git.kernel.org/stable/c/927794a02169778c9c2e7b25c768ab3ea8c1dc03 (opens in a new tab)
- git.kernel.org/stable/c/4c21fa60a6f4606f6214a38f50612b17b2f738f5 (opens in a new tab)
- git.kernel.org/stable/c/f97e75fa4e12b0aa0224e83fcbda8853ac2adf36 (opens in a new tab)
- git.kernel.org/stable/c/0184747b552d6b5a14db3b7fcc3b792ce64dedd1 (opens in a new tab)
- git.kernel.org/stable/c/a2576ae9a35c078e488f2c573e9e6821d651fbbe (opens in a new tab)
- git.kernel.org/stable/c/4530b3660d396a646aad91a787b6ab37cf604b53 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2024-26773 (opens in a new tab)
- ubuntu.com/security/notices/USN-6820-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-6821-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-6821-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-6828-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-6820-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-6821-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-6831-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-6821-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-6867-1 (opens in a new tab)