CVE-2026-43068: Linux kernel · ext4: avoid allocate block from corrupted group in ext4_mb_find_by_goal()
Affects Linux kernelSource CVE Database V5
Not known to be exploited · fixed in ffc0a282462d45fee5957621be5afa29752f3b6d : patch Linux kernel soon.
Data as of 6 Nov 2026, 16:18 UTC
Rated High by Threat Radar's AI analysis · No CVSS score from NVD or the CNA
Thin evidence
One scorer or none- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Limited control over the software or limited information exposure
CISA SSVC assessment, 2026-11-06.
- Patch
- Available – fixed in ffc0a282462d45fee5957621be5afa29752f3b6d, fea6b2e250ff48f10d166011b57a8516ae5438c9, 9370207b36d26e45a8c8ef0500706d37036edd6b +5
Exploitation evidence
Disclosed: evidence found.
CVE published 5 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 6 Nov 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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AI-suggested
A fix is available in the Linux kernel as indicated by multiple commits addressing the issue. Users should update to a Linux kernel version that includes these fixes. Since this is a kernel-level vulnerability, applying the official patches or upgrading to a fixed kernel release is the recommended mitigation.
Description
CVE-2026-43068 is a vulnerability in the Linux kernel's ext4 filesystem code where block allocation can occur from a corrupted block group in the ext4_mb_find_by_goal() function. This can lead to delayed block allocation failures and potential data loss, as indicated by error logs showing 'Delayed block allocation failed' and 'This should not happen!! Data will be lost'. The issue arises because the code does not properly prevent allocation from corrupted block groups after certain commits changed error handling behavior.
References
- git.kernel.org/stable/c/fea6b2e250ff48f10d166011b57a8516ae5438c9 (opens in a new tab)
- git.kernel.org/stable/c/0b84571c886719823d537f05f4f07cad6357c4b7 (opens in a new tab)
- git.kernel.org/stable/c/ffc0a282462d45fee5957621be5afa29752f3b6d (opens in a new tab)
- git.kernel.org/stable/c/2d31a5073f86a177edf44015e0dedb0c47cfd6d8 (opens in a new tab)
- git.kernel.org/stable/c/9370207b36d26e45a8c8ef0500706d37036edd6b (opens in a new tab)
- git.kernel.org/stable/c/1895f7904be71c48f1e6f338b28f24dabd6b8aeb (opens in a new tab)
- git.kernel.org/stable/c/1c0d7c4cde38a887c6d74e0c89ddb25226943c78 (opens in a new tab)
- git.kernel.org/stable/c/46066e3a06647c5b186cc6334409722622d05c44 (opens in a new tab)