CVE-2026-63858: Linux

High severity, CVSS 7.8. EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: add hook transactions for device deletions Restore the flag that indicates that the hook is going away, ie. NFT_HOOK_REMOVE, but add a new transaction object to track deletion of hooks without altering the basechain/flowtable hook_list during the preparation phase. The existing approach that moves the hook from the basechain/flowtable hook_list to transaction hook_list breaks netlink dump path readers of this RCU-protected list. It should be possible use an array for nft_trans_hook to store the deleted hooks to compact the representation but I am not expecting many hook object, specially now that wildcard support for devices is in place. Note that the nft_trans_chain_hooks() list contains a list of struct nft_trans_hook objects for DELCHAIN and DELFLOWTABLE commands, while this list stores struct nft_hook objects for NEWCHAIN and NEWFLOWTABLE. Note that new commands can be updated to use nft_trans_hook for consistency. This patch also adapts the event notification path to deal with the list of hook transactions.

Affected products

• Linux Linux: from 5.10.122, before 5.11 (fixed in 5.11); from 5.15.47, before 5.16 (fixed in 5.16); from 5.17.15, before 5.18 (fixed in 5.18); from 5.18.4, before 5.19 (fixed in 5.19); from 5.19, before 7.0.10 (fixed in 7.0.10)

Published 2026-07-19. Last modified 2026-07-27.