CVE-2026-43424

Description

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_tcm: Fix NULL pointer dereferences in nexus handling The `tpg->tpg_nexus` pointer in the USB Target driver is dynamically managed and tied to userspace configuration via ConfigFS. It can be NULL if the USB host sends requests before the nexus is fully established or immediately after it is dropped. Currently, functions like `bot_submit_command()` and the data transfer paths retrieve `tv_nexus = tpg->tpg_nexus` and immediately dereference `tv_nexus->tvn_se_sess` without any validation. If a malicious or misconfigured USB host sends a BOT (Bulk-Only Transport) command during this race window, it triggers a NULL pointer dereference, leading to a kernel panic (local DoS). This exposes an inconsistent API usage within the module, as peer functions like `usbg_submit_command()` and `bot_send_bad_response()` correctly implement a NULL check for `tv_nexus` before proceeding. Fix this by bringing consistency to the nexus handling. Add the missing `if (!tv_nexus)` checks to the vulnerable BOT command and request processing paths, aborting the command gracefully with an error instead of crashing the system.

Gravité et risque d'exploitation

CVE-2026-43424 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 0.16 %, ce qui la place devant 5.1 % des CVE référencées.

Que faire ?

• Vérifiez si Linux (versions <=6.1.*, <=6.12.*, <679d9535aeb15c10bce89c44102004b96624d706, <d146f27758049fa55ae4c53785a852d3cf7a18d6, 6.12.78, 0, 7.0, c52661d60f636d17e26ad834457db333bd1df494, 3.5, 6.18.19, <=5.10.*, <=6.6.*, <=6.19.*, 6.19.9, <3.5, <b9fde507355342a2d64225d582dc8b98ff5ecb19, <3d309b37633c4a847fc149939a2c9576f1aa1065, <=6.18.*, <f962ca3b020e13d6714f27e8c36fe742441c58d1, <b9b26d7f3aa288cfa54a7bc68612bab1f153f156, 6.1.167, <=*, 5.10.253, <2a2ef846a54a06c33b5c2d4b0d918583e1e7c0b7, 6.6.130) 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/b9b26d7f3aa288cfa54a7bc68612bab1f153f156
• https://git.kernel.org/stable/c/2a2ef846a54a06c33b5c2d4b0d918583e1e7c0b7
• https://git.kernel.org/stable/c/d146f27758049fa55ae4c53785a852d3cf7a18d6
• https://git.kernel.org/stable/c/f962ca3b020e13d6714f27e8c36fe742441c58d1
• https://git.kernel.org/stable/c/679d9535aeb15c10bce89c44102004b96624d706
• https://git.kernel.org/stable/c/3d309b37633c4a847fc149939a2c9576f1aa1065
• https://git.kernel.org/stable/c/b9fde507355342a2d64225d582dc8b98ff5ecb19