CVE-2026-46057 landlock: Fix LOG_SUBDOMAINS_OFF inheritance across fork()
A flaw in Linux kernel Landlock allows child processes to bypass log muting, potentially exposing sensitive audit records.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-46057?
CVE-2026-46057 is a low-severity vulnerability in Linux kernel, published on 27 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
landlock: Fix LOG_SUBDOMAINS_OFF inheritance across fork()
hook_cred_transfer() only copies the Landlock security blob when the source credential has a domain. This is inconsistent with landlock_restrict_self() which can set LOG_SUBDOMAINS_OFF on a credential without creating a domain (via the ruleset_fd=-1 path): the field is committed but not preserved across fork() because the child's prepare_creds() calls hook_cred_transfer() which skips the copy when domain is NULL.
This breaks the documented use case where a process mutes subdomain logs before forking sandboxed children: the children lose the muting and their domains produce unexpected audit records.
Fix this by unconditionally copying the Landlock credential blob.
Which versions are affected by CVE-2026-46057?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-46057?
Apply the vendor's patch.
Is CVE-2026-46057 being exploited?
There is no known exploitation of CVE-2026-46057 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-46057, DEBIAN-CVE-2026-46057, GHSA-q738-wcrr-x4xx, UBUNTU-CVE-2026-46057.