CVE-2024-26835: 
Linux Kernel vulnerability analysis and mitigation

CVE-2024-26835 affects the Linux kernel's netfilter/nf_tables component. The vulnerability was discovered and disclosed on April 17, 2024, and involves a failure to properly handle hook registration failures in the nf_tables subsystem. The issue affects various Linux kernel versions and distributions including Ubuntu and Debian systems (NVD).

The vulnerability occurs when hook registration fails during memory pressure situations in the nf_tables subsystem. When this happens, the table can end up marked as active but with no registered hooks. During table/base chain deletion, nf_tables attempts to unregister the hook again, which results in a warning splat from the nftables core. The issue was traced to a missing dormant flag setting after hook registration failure (Kernel Commit).

The vulnerability can lead to system warnings and potential system instability when using netfilter/nf_tables functionality, particularly during table/base chain deletion operations after a failed hook registration (Ubuntu Security).

The vulnerability requires specific conditions involving memory pressure during nf_tables hook registration. There are no known exploits in the wild, and the issue primarily manifests as a system warning rather than a direct security compromise (NVD).

The issue has been fixed in various Linux kernel versions through a patch that properly sets the dormant flag when hook registration fails. The fix has been backported to multiple stable kernel versions and distributions. Ubuntu has released fixes for affected versions including 22.04 LTS (5.15.0-112.122) and 20.04 LTS (5.4.0-186.206) (Ubuntu Security).