CVE-2026-43076
HighIn the Linux kernel, the following vulnerability has been resolved: ocfs2: validate inline data i_size during inode read When reading an inode from disk, ocfs2_validate_inode_block() performs various sanity checks but does not validate the size of inline data. If the filesystem is corrupted, an inode's i_size can exceed the actual inline data capacity (id_count). This causes ocfs2_dir_foreach_blk_id() to iterate beyond the inline data buffer, triggering a use-after-free when accessing directory entries from freed memory. In the syzbot report: - i_size was 1099511627576 bytes (~1TB) - Actual inline data capacity (id_count) is typically <256 bytes - A garbage rec_len (54648) caused ctx->pos to jump out of bounds - This triggered a UAF in ocfs2_check_dir_entry() Fix by adding a validation check in ocfs2_validate_inode_block() to ensure inodes with inline data have i_size <= id_count. This catches the corruption early during inode read and prevents all downstream code from operating on invalid data.
CVSS 3.1 score
7.8
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Weakness type
CWE-416CVE-2026-43076 is a Use After Free vulnerability
What is Use After Free?
The product references memory after it has been freed, which may cause it to crash, use unexpected values, or execute code. Learn more on MITRE CWE
Affected versions
Linux kernel versions
2.6.24
and later are affected. Fixed in
5.10.258,
5.15.209,
6.1.175,
6.6.136,
6.12.83,
6.18.24,
6.19.14,
7.0
and their respective stable series.
References
The following references provide additional information about CVE-2026-43076 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.
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PatchKernel patch commithttps://git.kernel.org/stable/c/131c0b573e1b467b7d553e9ff38003f1acd8f5f2
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PatchKernel patch commithttps://git.kernel.org/stable/c/1524af3685b35feac76662cc551cbc37bd14775f
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PatchKernel patch commithttps://git.kernel.org/stable/c/37f074e65f24f10f8d8df224a572e4cb9e6faf63
Frequently asked questions
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What is CVE-2026-43076?
CVE-2026-43076 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10 , classified as an Use After Free flaw (CWE-416) . It affects Linux kernel versions from 2.6.24 onward and has been patched in 5.10.258, 5.15.209, 6.1.175 and others. CVE-2026-43076 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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What is the CVSS score for CVE-2026-43076?
CVE-2026-43076 has a CVSS score of 7.8 out of 10, rated High severity (CVSS 3.1). The vector string is
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. -
Is there a patch available for CVE-2026-43076?
Yes — CVE-2026-43076 has been patched. Fixed versions include 5.10.258, 5.15.209, 6.1.175 and others. If you are running Linux kernel 2.6.24 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-43076 actively exploited?
No — CVE-2026-43076 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
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What is Use After Free (CWE-416)?
The product references memory after it has been freed, which may cause it to crash, use unexpected values, or execute code. View CWE-416 on MITRE CWE →