CVE-2025-38478

Description

In the Linux kernel, the following vulnerability has been resolved: comedi: Fix initialization of data for instructions that write to subdevice Some Comedi subdevice instruction handlers are known to access instruction data elements beyond the first `insn->n` elements in some cases. The `do_insn_ioctl()` and `do_insnlist_ioctl()` functions allocate at least `MIN_SAMPLES` (16) data elements to deal with this, but they do not initialize all of that. For Comedi instruction codes that write to the subdevice, the first `insn->n` data elements are copied from user-space, but the remaining elements are left uninitialized. That could be a problem if the subdevice instruction handler reads the uninitialized data. Ensure that the first `MIN_SAMPLES` elements are initialized before calling these instruction handlers, filling the uncopied elements with 0. For `do_insnlist_ioctl()`, the same data buffer elements are used for handling a list of instructions, so ensure the first `MIN_SAMPLES` elements are initialized for each instruction that writes to the subdevice.

Gravité et risque d'exploitation

CVE-2025-38478 obtient un score CVSS de 7.8/10, soit une gravité élevée. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.18 %, ce qui la place devant 7.0 % des CVE référencées.

Que faire ?

• Vérifiez si Linux (versions 6.1.147, <=6.1.*, <2.6.29, <=6.12.*, 6.6.100, 0, ed9eccbe8970f6eedc1b978c157caf1251a896d4, <6f38c6380c3b38a05032b8881e41137385a6ce02, <=6.15.*, 5.4.297, 2.6.29, <673ee92bd2d31055bca98a1d96b653f5284289c4, 6.15.8, <=5.10.*, <=6.6.*, <46d8c744136ce2454aa4c35c138cc06817f92b8e, 5.15.190, <13e4d9038a1e869445a996a3f604a84ef52fe8f4, <020eed5681d0f9bced73970368078a92d6cfaa9c, <=5.4.*, 6.16, <c42116dc70af6664526f7aa82cf937824ab42649, <fe8713fb4e4e82a4f91910d9a41bf0613e69a0b9, 6.12.40, 5.10.241, <=*, <=5.15.*, <d3436638738ace8f101af7bdee2eae1bc38e9b29) 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/6f38c6380c3b38a05032b8881e41137385a6ce02
• https://git.kernel.org/stable/c/13e4d9038a1e869445a996a3f604a84ef52fe8f4
• https://git.kernel.org/stable/c/020eed5681d0f9bced73970368078a92d6cfaa9c
• https://git.kernel.org/stable/c/d3436638738ace8f101af7bdee2eae1bc38e9b29
• https://git.kernel.org/stable/c/673ee92bd2d31055bca98a1d96b653f5284289c4
• https://git.kernel.org/stable/c/c42116dc70af6664526f7aa82cf937824ab42649
• https://git.kernel.org/stable/c/fe8713fb4e4e82a4f91910d9a41bf0613e69a0b9
• https://git.kernel.org/stable/c/46d8c744136ce2454aa4c35c138cc06817f92b8e