Vulnerability in Linux
CVE-2026-63858
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.
EPSS: 0.001 (2.4th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Linux — versions b6d9014a3335194590abdd2a2471ef5147a67645, 7a248f9c74f9f62799718c12efd9e9e391d60b6f, f275989ad04159dbfc62cefb65ba9c5ba1d7c34f
References
Frequently asked questions
- What is CVE-2026-63858?
- CVE-2026-63858 is a high-severity vulnerability in Linux. CVSS score: 7.8/10. Published 2026-07-19.
- How severe is CVE-2026-63858?
- High severity. CVSS v3 base score is 7.8 out of 10.