CVE-2026-88838 Busybox: busybox: non-root mount option filter bypass allows clearing fstab security restrictions
A non-root user can bypass fstab security restrictions in BusyBox mount, overriding nosuid, nodev, and noexec protections to potentially escalate privileges.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-88838?
CVE-2026-88838 is a medium-severity vulnerability in Red Hat Hardened Images, published on 13 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
A flaw was found in BusyBox's mount utility. A non-root user can bypass mount security restrictions set in /etc/fstab by specifying clearing-mask options on the command line. These options pass the non-root flag filter and are merged with fstab options as strings; when the combined options are re-parsed, clearing options can override nosuid, nodev, and noexec protections the administrator intended to enforce.
Weakness: CWE-693
Which versions are affected by CVE-2026-88838?
How do I fix CVE-2026-88838?
No fix has been published for CVE-2026-88838 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-88838 being exploited?
There is no known exploitation of CVE-2026-88838 in the wild and no public exploit code.
Sources
Also known as AZL-108324, BELL-CVE-2026-88838, DEBIAN-CVE-2026-88838, GHSA-wq8x-j557-xr3g, UBUNTU-CVE-2026-88838.