CVE-2026-89948

Description

In the Linux kernel, the following vulnerability has been resolved: batman-adv: bla: fix freeing of claims on meshif deletion When the mesh interface is getting deleted, then batadv_bla_del_backbone_claims() (via batadv_bla_purge_backbone_gw()) could make sure that all claims gets removed. But this function is only executed when bat_priv->bla.claim_hash is not NULL. And since batadv_bla_free() is always setting it to NULL before it is (indirectly) called, it was never actually executed. But the batadv_bla_purge_claims() -> batadv_handle_unclaim() is at the moment too fragile because the BLA code is not handling the rehashing in batadv_bla_update_orig_address(). The stored backbone address doesn't have to be the one actually used for the hash bucket selection during the initial adding of the backbone. The batadv_handle_unclaim() can therefore fail to find the respective backbone for the unclaim and then stop the deletion. But the actual backbone_gw object is not needed for the unclaim because all relevant information is always provided by the caller. And the check for the existence of the backbone_gw doesn't provide any additional security check for the deletion of a claim.

Gravité et risque d'exploitation

CVE-2026-89948 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 0.21 %, ce qui la place devant 10.7 % des CVE référencées.

Que faire ?

• Vérifiez si Linux (versions <=6.1.*, <=6.12.*, <baeb1a28fd8e2f68193650d3664a8cd1adfd85c6, 5.15.221, 5.10.270, 0, 6.1.188, 6.18.51, <9a0c47023d3254048a1588534755d4476bcc3abc, 3.5, <=5.10.*, <f50edb69082a8ba990cc23d642089829f99afe6a, <=6.6.*, <871acdf97f64cee8398f72b88b89e8b4f4816dbe, 7.2.5, 6.6.157, <aacffa780a37e06cd5a13d33740a6e96c3a67e6c, <844a95a734f178d56c7acce14c5cce2cecff7e1a, <3.5, <=6.18.*, 6.12.110, <=7.2.*, <=*, <=5.15.*, <76aedcde5a2489cc971d4d1e396e784a49565e96, 23721387c409087fd3b97e274f34d3ddc0970b74, <8d128c932bced74e3b1625ba3d7c78ef122a88a7, 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/844a95a734f178d56c7acce14c5cce2cecff7e1a
• https://git.kernel.org/stable/c/baeb1a28fd8e2f68193650d3664a8cd1adfd85c6
• https://git.kernel.org/stable/c/aacffa780a37e06cd5a13d33740a6e96c3a67e6c
• https://git.kernel.org/stable/c/76aedcde5a2489cc971d4d1e396e784a49565e96
• https://git.kernel.org/stable/c/f50edb69082a8ba990cc23d642089829f99afe6a
• https://git.kernel.org/stable/c/871acdf97f64cee8398f72b88b89e8b4f4816dbe
• https://git.kernel.org/stable/c/9a0c47023d3254048a1588534755d4476bcc3abc
• https://git.kernel.org/stable/c/8d128c932bced74e3b1625ba3d7c78ef122a88a7