CVE-2026-80854
Vulnérabilité non évaluée dans Linux (Linux)
Description
In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_tcm: keep port count until LUN teardown completes tcm_usbg_drop_nexus() permits session removal once tpg_port_count reaches zero. However, usbg_port_unlink() currently decrements that count from the fabric_pre_unlink() callback, before core_dev_del_lun() waits for active se_lun references to drain. If removal of the last LUN races a nexus removal, the latter can observe a zero port count and call target_remove_session(). This frees sess_cmd_map while an in-flight struct usbg_cmd, including its work item, can still be accessed. Overlapping the last-LUN unlink with nexus removal reproduces this lifetime violation as a DEBUG_OBJECTS "free active" warning for usbg_cmd_work, followed by a target-core BUG/Oops. The generic target-core unlink path has no callback after core_dev_del_lun() completes. Add an optional fabric_post_unlink() callback and use it for the f_tcm port count. The count now remains nonzero until core_dev_del_lun() has finished draining active LUN references, preventing nexus removal from freeing the session during command completion.
Gravité et risque d'exploitation
CVE-2026-80854 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 7.3 % des CVE référencées.
Que faire ?
- Vérifiez si Linux (versions <=6.1.*, <=6.12.*, 6.6.156, <bbd6aa311a9f4dd17822c7557451458d3d2e980b, 5.10.269, <c494c5562ca69b61a82f566e3b87a445d2c28929, 0, c52661d60f636d17e26ad834457db333bd1df494, <=7.1.*, <c39d0916da47d94909391876c9e5bd429ea7b1b9, <c1f359d9a5efed458946063de65ddbeaacc4f165, 3.5, <=5.10.*, <=6.6.*, <3.5, <=6.18.*, <178f59a0bccd3f66cdfa5184310f31a58b7257c4, <=7.2.*, <2efbfd42441d3ef8137aff2d59e9835e1d5ae780, 5.15.220, 7.1.13, 6.18.49, <=*, <=5.15.*, 6.12.108, <85aa61fedcb4eb13f3dc5db73f6dc359f41f5d95, <eaa96a8458f54d6cf0954242ab8b1df2a6fccafa, <ad6f0375d2e93a1d8c015463e5e92dfcb26e311b, 6.1.187, 7.2.3, 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/c494c5562ca69b61a82f566e3b87a445d2c28929
- https://git.kernel.org/stable/c/c1f359d9a5efed458946063de65ddbeaacc4f165
- https://git.kernel.org/stable/c/178f59a0bccd3f66cdfa5184310f31a58b7257c4
- https://git.kernel.org/stable/c/ad6f0375d2e93a1d8c015463e5e92dfcb26e311b
- https://git.kernel.org/stable/c/2efbfd42441d3ef8137aff2d59e9835e1d5ae780
- https://git.kernel.org/stable/c/85aa61fedcb4eb13f3dc5db73f6dc359f41f5d95
- https://git.kernel.org/stable/c/bbd6aa311a9f4dd17822c7557451458d3d2e980b
- https://git.kernel.org/stable/c/eaa96a8458f54d6cf0954242ab8b1df2a6fccafa
- https://git.kernel.org/stable/c/c39d0916da47d94909391876c9e5bd429ea7b1b9