CVE-2025-68339

Description

In the Linux kernel, the following vulnerability has been resolved: atm/fore200e: Fix possible data race in fore200e_open() Protect access to fore200e->available_cell_rate with rate_mtx lock in the error handling path of fore200e_open() to prevent a data race. The field fore200e->available_cell_rate is a shared resource used to track available bandwidth. It is concurrently accessed by fore200e_open(), fore200e_close(), and fore200e_change_qos(). In fore200e_open(), the lock rate_mtx is correctly held when subtracting vcc->qos.txtp.max_pcr from available_cell_rate to reserve bandwidth. However, if the subsequent call to fore200e_activate_vcin() fails, the function restores the reserved bandwidth by adding back to available_cell_rate without holding the lock. This introduces a race condition because available_cell_rate is a global device resource shared across all VCCs. If the error path in fore200e_open() executes concurrently with operations like fore200e_close() or fore200e_change_qos() on other VCCs, a read-modify-write race occurs. Specifically, the error path reads the rate without the lock. If another CPU acquires the lock and modifies the rate (e.g., releasing bandwidth in fore200e_close()) between this read and the subsequent write, the error path will overwrite the concurrent update with a stale value. This results in incorrect bandwidth accounting.

Gravité et risque d'exploitation

CVE-2025-68339 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 0.19 %, ce qui la place devant 8.3 % des CVE référencées.

Que faire ?

• Vérifiez si Linux (versions <=6.1.*, <=6.12.*, 2.6.12, <9917ba597cf95f307778e495f71ff25a5064d167, <667ac868823224374f819500adc5baa2889c7bc5, 0, <82fca3d8a4a34667f01ec2351a607135249c9cff, <6610361458e7eb6502dd3182f586f91fcc218039, <2.6.12, 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, <ed34c70d88e2b8b9bc6c3ede88751186d6c6d5d1, 6.18, 5.10.247, <=5.10.*, <=6.6.*, <1b60f42a639999c37da7f1fbfa1ad29cf4cbdd2d, <bd1415efbab507b9b995918105eef953013449dd, 5.15.197, 6.1.159, 6.6.119, 6.17.11, <=*, <=5.15.*, <=6.17.*, 6.12.61) 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/1b60f42a639999c37da7f1fbfa1ad29cf4cbdd2d
• https://git.kernel.org/stable/c/bd1415efbab507b9b995918105eef953013449dd
• https://git.kernel.org/stable/c/ed34c70d88e2b8b9bc6c3ede88751186d6c6d5d1
• https://git.kernel.org/stable/c/9917ba597cf95f307778e495f71ff25a5064d167
• https://git.kernel.org/stable/c/667ac868823224374f819500adc5baa2889c7bc5
• https://git.kernel.org/stable/c/6610361458e7eb6502dd3182f586f91fcc218039
• https://git.kernel.org/stable/c/82fca3d8a4a34667f01ec2351a607135249c9cff