CVE-2026-98484
Vulnérabilité non évaluée dans Linux (Linux)
Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: skip expired catchall elements on insert and delete nft_setelem_catchall_insert() looks up duplicates with nft_set_elem_active() only, while nft_set_catchall_lookup() and the dump path additionally skip expired elements. Once a catchall element with a timeout expires, this predicate drift makes it invisible to userspace dumps, yet it still blocks re-insertion: with NLM_F_EXCL the request fails with -EEXIST, and without it the request reports success but silently inserts nothing. The stale entry only goes away when the (user-tunable) gc interval elapses, so the catchall rule may silently stop matching for an arbitrarily long time after its first expiration. The delete path shows the same drift: nft_setelem_catchall_deactivate() picks the first active-next entry in the catchall list, so with an expired entry still pending GC it retires the stale entry instead of the fresh one, and it deactivates an element that userspace no longer sees instead of failing with -ENOENT. Align both walks with the lookup and dump predicates: only an element that is active and not expired counts as a duplicate or delete candidate, using the per-netns timestamp taken at transaction start, in line with the set backend .insert/.deactivate and catchall GC sync paths.
Gravité et risque d'exploitation
CVE-2026-98484 obtient un score CVSS de 0.0/10, soit une gravité non évaluée.
Que faire ?
- Vérifiez si Linux (versions <4fb8b1ccc475651e480e509de126bb9ce7f3cff9, aaa31047a6d25da0fa101da1ed544e1247949b40, <=*, <=6.12.*, 5.13, <5.13, 6.12.112, <=6.18.*, <70194dc37670bd08e44b471389861cc01bd3a3c9, 6.18.55, 0, <=7.2.*, <2f07da3881525f7cbfed1ced2796c71a201505b9, <12cf803edfffef96f6415f0b5dbc7ec88842ea0f, 7.2.9, 7.3) est présent sur votre parc.
- Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
- À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
- Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.