CVE-2026-98622
Vulnérabilité non évaluée dans Linux (Linux)
Description
In the Linux kernel, the following vulnerability has been resolved: net/sched: act_ct: don't WARN on benign flow_offload_alloc() failure flow_offload_alloc() returns NULL when the conntrack entry is dying (e.g. raced with a conntrack flush) or when the GFP_ATOMIC allocation fails; both are expected under load and neither is a kernel bug. This path runs from softirq on every committed packet, so with panic_on_warn=1 an unprivileged user can panic the box just by racing a conntrack flush against a `tc ... action ct commit` classifier. Reproduced with a custom repro under QEMU: a small, fixed set of UDP flows through `tc filter ... action ct commit` on lo, raced against threads flooding bare ctnetlink CT_DELETE (flush) requests. Hits WARNING: net/sched/act_ct.c:437 (tcf_ct_flow_table_add(), inlined into tcf_ct_act() in this build) within ~15s on the unpatched kernel; same setup is clean on the patched kernel. The fix itself is behavior-preserving: both branches already did `goto err_alloc` before and after, only the WARN is removed.
Gravité et risque d'exploitation
CVE-2026-98622 obtient un score CVSS de 0.0/10, soit une gravité non évaluée. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.18 %, ce qui la place devant 6.8 % des CVE référencées.
Que faire ?
- Vérifiez si Linux (versions <=6.1.*, <424ba52c0058deeb940d02cba52eb0aeb288db33, <=6.12.*, 6.18.55, 0, <00734f3684fcec42c319bedfe68a5d357c720b53, 6.12.112, <5.7, 5.10.271, 6.6.158, <d805560ad69cb266d669341ca01e26bffb0d2c67, <=5.10.*, <=6.6.*, 6.1.189, <d512c484bd93a5f2794aa03c9faeb7bcb82dbd4a, <47abe7a5c4eb53269aca3506446f851572a059a3, <=6.18.*, 5.15.222, <=7.2.*, <e8fcf3f08834e939b797311742ee72b1e2a08096, <650787233c2fd6e515a7c5f371019a9fa080ccd2, 7.2.9, 5.7, <=*, <af475f599270e59313552e6c6f3af8507da672b8, <=5.15.*, 64ff70b80fd403110b67dd9f7184a604fdb0da43, 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.
Références
- https://git.kernel.org/stable/c/e8fcf3f08834e939b797311742ee72b1e2a08096
- https://git.kernel.org/stable/c/af475f599270e59313552e6c6f3af8507da672b8
- https://git.kernel.org/stable/c/424ba52c0058deeb940d02cba52eb0aeb288db33
- https://git.kernel.org/stable/c/d512c484bd93a5f2794aa03c9faeb7bcb82dbd4a
- https://git.kernel.org/stable/c/d805560ad69cb266d669341ca01e26bffb0d2c67
- https://git.kernel.org/stable/c/00734f3684fcec42c319bedfe68a5d357c720b53
- https://git.kernel.org/stable/c/650787233c2fd6e515a7c5f371019a9fa080ccd2
- https://git.kernel.org/stable/c/47abe7a5c4eb53269aca3506446f851572a059a3
