Out-of-bounds read in Linux kernel - CVE-2026-53390

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

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.

Linux kernel
openEuler
Ubuntu
bpftool
python3-perf-debuginfo
python3-perf
perf-debuginfo
perf
kernel-tools-devel
kernel-tools-debuginfo
kernel-tools
kernel-source
kernel-headers
kernel-devel
kernel-debugsource
kernel-debuginfo
bpftool-debuginfo
kernel
linux (Ubuntu package)
linux-gcp-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
bpftool - update to 5.10.0-328.0.0.229
python3-perf-debuginfo - update to 5.10.0-328.0.0.229
python3-perf - update to 5.10.0-328.0.0.229
perf-debuginfo - update to 5.10.0-328.0.0.229
perf - update to 5.10.0-328.0.0.229
kernel-tools-devel - update to 5.10.0-328.0.0.229
kernel-tools-debuginfo - update to 5.10.0-328.0.0.229
kernel-tools - update to 5.10.0-328.0.0.229
kernel-source - update to 5.10.0-328.0.0.229
kernel-headers - update to 5.10.0-328.0.0.229
kernel-devel - update to 5.10.0-328.0.0.229
kernel-debugsource - update to 5.10.0-328.0.0.229
kernel-debuginfo - update to 5.10.0-328.0.0.229
bpftool-debuginfo - update to 5.10.0-328.0.0.229
kernel - update to 5.10.0-328.0.0.229
linux (Ubuntu package) - addressed in versions 7.0.0-31.31, 7.0.0-31.31.1, 7.0.0-31.31~24.04.1, 7.0.0-1006.7, 7.0.0-1011.11~24.04.1, 7.0.0-1012.12, 7.0.0-1012.12~24.04.1
linux-gcp-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1013.13

• 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

• Out-of-bounds read in Linux kernel smb server
• openEuler 22.03 LTS SP4 update for kernel
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux
• Ubuntu update for linux-gcp-7.0