CVE-2024-26809: 
Linux Kernel vulnerability analysis and mitigation

CVE-2024-26809 is a vulnerability discovered in the Linux kernel's Netfilter subsystem, specifically in the nft_set_pipapo component. The vulnerability was disclosed on April 4, 2024, affecting the netfilter subsystem's element handling in the clone path (NVD).

The vulnerability occurs in the netfilter: nft_set_pipapo component where elements could potentially be destroyed twice due to improper handling in the clone path. The issue specifically relates to the lookup table's current view in the clone, which already provides a complete view but wasn't being properly utilized in the destroy path. This vulnerability requires the fix that came after commit 212ed75dc5fb ("netfilter: nf_tables: integrate pipapo into commit protocol") and 9827a0e6e23b ("netfilter: nft_set_pipapo: release elements in clone from abort path") (Kernel Commit).

The vulnerability could potentially lead to system compromise if exploited, as indicated by Ubuntu's high priority rating for this issue (Ubuntu).

The issue has been fixed in various Linux kernel versions across different distributions. Ubuntu has released patches for multiple versions including 24.04 LTS (6.8.0-35.35), 23.10 (6.5.0-42.42), and 22.04 LTS (5.15.0-112.122). The fix involves modifying the element destruction process in the clone path to prevent double destruction of elements (Ubuntu Security Notice).