SB20260824247 - Improper access control in Linux kernel crypto
Published: August 24, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Improper access control (CVE-ID: CVE-2026-74595)
CWE-ID: CWE-284 - Improper Access Control
CVSSv4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows a local user to bypass owner checks and set an encryption policy on a file.
The vulnerability exists due to improper access control in fscrypt_ioctl_set_policy() when handling ioctl requests on idmapped mounts. A local user can issue a crafted ioctl on an idmapped mount to bypass owner checks and set an encryption policy on a file.
The issue occurs because the check uses the unmapped on-disk owner rather than the mapped owner on mounts that support idmapping.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/0baeb730044981f5ec5fb7d62a3763835ea606f6
- https://git.kernel.org/stable/c/174633a468817a49bd474bcfc9067c84e54efe68
- https://git.kernel.org/stable/c/33b7e810ce09955aa02f3b632455cf5e7ac990a9
- https://git.kernel.org/stable/c/653e888a24c87b8bbeab44d7e558a1c1a3641088
- https://git.kernel.org/stable/c/6a67c460b12315033268dce597546984fe5739e7
- https://git.kernel.org/stable/c/98516ba8b817f34e86bdd7a5b7a383cff75c3ddf
- https://git.kernel.org/stable/c/cf6c993c0feca7984797e634deba3c80342e199a