Copyright © 2012 Red Hat, Inc. All rights reserved. Moderate 2026-08-22T00:00:00 kernel: fscrypt: use the mount idmap for the owner check in fscrypt_ioctl_set_policy() 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H CWE-628

In the Linux kernel, the following vulnerability has been resolved: fscrypt: use the mount idmap for the owner check in fscrypt_ioctl_set_policy() fscrypt_ioctl_set_policy() calls inode_owner_or_capable() with &nop_mnt_idmap before allowing an encryption policy to be set, instead of the idmap of the mount the ioctl was issued on. fscrypt is used by filesystems that support idmapped mounts (e.g. ext4, f2fs), so on such a mount this compares the caller's fsuid against the unmapped on-disk owner rather than the mapped owner: the actual owner can be wrongly denied with -EACCES and an unrelated caller wrongly allowed. Use file_mnt_idmap(filp) instead.

A flaw was found in the Linux kernel's fscrypt component. When setting an encryption policy on an idmapped mount, the `fscrypt_ioctl_set_policy()` function incorrectly performs an owner check. This vulnerability can lead to legitimate users being denied access to set encryption policies, while unauthorized users might be wrongly permitted to do so, resulting in an access control bypass.

Red Hat Enterprise Linux 10 Fix deferred kernel Red Hat Enterprise Linux 6 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel-rt Red Hat Enterprise Linux 8 Not affected kernel Red Hat Enterprise Linux 8 Not affected kernel-rt Red Hat Enterprise Linux 9 Fix deferred kernel Red Hat Enterprise Linux 9 Fix deferred kernel-rt https://www.cve.org/CVERecord?id=CVE-2026-74595 https://nvd.nist.gov/vuln/detail/CVE-2026-74595 https://lore.kernel.org/linux-cve-announce/2026082214-CVE-2026-74595-9491@gregkh/T