CVE-2026-89786

9.1 CRITICAL

Published 2026-09-16 · Updated 2026-09-16

AI risk analysis

Summary: This vulnerability in the ext4 file system of the Linux kernel allows an attacker to trigger a slab-out-of-bounds read, potentially leading to information disclosure.
Exploitability: Exploitation requires specific conditions, such as a crafted directory structure, and is considered moderately difficult.
Blast radius: If exploited, the vulnerability could lead to sensitive information disclosure, impacting system security.
Detection: No reliable host or network indicator is derivable from the published description.
Prioritized remediation: Upgrade to the fixed version 5.19.10 or later.

info-disckernelfsext4

Analysis generated locally by qwen2.5:7b-instruct (no data left the box). AI-assisted — verify against primary sources before acting.

NVD description

In the Linux kernel, the following vulnerability has been resolved: ext4: fix out-of-bounds read in ext4_read_inline_dir() ext4_read_inline_dir() can read a dirent header past the end of its inline buffer, triggering a slab-out-of-bounds read during getdents64(): BUG: KASAN: slab-out-of-bounds in __ext4_check_dir_entry Read of size 2 at addr ffff88800f3dd23c by task exploit/148 ... __ext4_check_dir_entry ext4_read_inline_dir iterate_dir The dirent payload lives in a buffer of exactly inline_size bytes: dir_buf = kmalloc(inline_size, GFP_NOFS); but iteration runs in a position space extra_offset bytes larger (extra_size = extra_offset + inline_size) so the synthetic "." and ".." land at their block-dir offsets. A dirent is formed at "dir_buf + pos - extra_offset", yet the ext4_check_dir_entry() length argument uses the larger extra_size. A position whose dirent header would extend past extra_size is therefore accepted, and the rescan loop's rec_len probe and ext4_check_dir_entry() dereference de->rec_len before the entry is rejected. Reject a position whose minimum-size dirent header would not fit within extra_size before forming de, in both the rescan and main loops, and pass inline_size rather than extra_size to ext4_check_dir_entry() so the length check matches the physical buffer.

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

All references

Source data: NVD (nvd.nist.gov), public domain. Exploit-DB.ai adds local AI analysis for defensive use only.

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