Out-of-bounds read in Linux kernel - CVE-2026-53390
Published: July 21, 2026
Vulnerability identifier: #VU138867
CSH Severity: Low
CVSS v4: 5.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-53390
CWE-ID: CWE-125
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to disclose sensitive information.
The vulnerability exists due to an out-of-bounds read in smb_check_perm_dacl() when processing a crafted security descriptor during an SMB2_CREATE access check. A remote user can store a crafted ACE via SMB2_SET_INFO to disclose sensitive information.
Exploitation is reachable on a share that uses ACL xattrs, and the malformed descriptor is processed on a subsequent access check.
Affected software
Linux kernel
How to mitigate CVE-2026-53390
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3
External References
- https://git.kernel.org/stable/c/1ef06004ed4bd6d3ed8c840d9d1a376b66d4935b
- https://git.kernel.org/stable/c/36599894fa8536fefdf1e296c0af71b8b7226859
- https://git.kernel.org/stable/c/7627ff8c4f9919f14de562b0160ab4ec9d80b1f7
- https://git.kernel.org/stable/c/988c93d3bba066d8669143e6ec30bb2be9608d53
- https://git.kernel.org/stable/c/d5c81a095c86fe507c032d08f3a8cfc518444927
- https://git.kernel.org/stable/c/e36e35660adb9b8ef1435ac359151dda5f094c55