CVE-2026-74500
Vulnérabilité non évaluée dans Linux (Linux)
Description
In the Linux kernel, the following vulnerability has been resolved: ALSA: usb-audio: fix stack info leak in RME Digiface status snd_rme_digiface_read_status() reads a four-word status block from the device into an uninitialised on-stack __le32 buf[4] and, whenever the vendor control-IN transfer does not return a negative error, copies all four words into the caller's status[]. snd_usb_ctl_msg() copies the full requested size back into the caller's buffer regardless of how many bytes the data stage actually delivered: buf = kmemdup(data, size, GFP_KERNEL); err = usb_control_msg(dev, pipe, request, requesttype, value, index, buf, size, timeout); memcpy(data, buf, size); usb_control_msg() returns the transferred length on a short control-IN, which is a non-negative value, and writes only that many bytes. The remainder of the copy back is the kmemdup()ed image of the caller's buffer, so a device answering with a short data stage leaves the trailing words of buf[] holding leftover kernel stack. The only guard in the caller is err < 0, so those words are stored into status[]. They then reach user space: snd_rme_digiface_get_status_val() selects a 16-bit halfword of status[] per the control's reg/mask, and the eight Digiface status controls together expose the whole 16-byte frame to an unprivileged reader of /dev/snd/controlC*. Zero-initialise the buffer so a short read yields zeros instead of stack residue. This mirrors snd_rme_get_status1(), which already clears its output word before the same kind of vendor read. Discovered by XBOW, triaged by Baul Lee <baul.lee@xbow.com>
Gravité et risque d'exploitation
CVE-2026-74500 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 0.17 %, ce qui la place devant 5.7 % des CVE référencées.
Que faire ?
- Vérifiez si Linux (versions 6.12, <=6.12.*, <b3a346d5c99dd73cf84711f2a43e42691990efd2, 0, <=7.1.*, <7ba01e0d3539d9cf0aef3e82938f1648147744cc, 6.12.103, 611a96f6acf2e74fe28cb90908a9c183862348ce, <6.12, 6.11.3, 50f63f11a6ddaa0d34574df72b3fa6ee257c057d, <441aaad150c57edaf57ee482a79a3bf4c5b7e353, <=6.18.*, 3089703ab71484a8b9a7641051181d11d60f870c, <6.11, <=*, 7.1.8, <98dbfbb38e297c25c5b0af4a9018d71ac25e8554, 6.10.14, 6.18.44, 7.2) 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.