CVE Catalog

CVE-2025-40269

HighCVSS 7.8
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.16%

5th percentile - higher than 5% of all known CVEs

Summary

In the ALSA USB-audio driver in the Linux kernel, the PCM packet size may exceed the wMaxPacketSize limit from the USB descriptor, causing a transfer buffer overflow. There is no validation of the packet size before use.

Risk Assessment

This vulnerability can lead to buffer overflow, potentially exploited to crash the system or execute arbitrary code via a malicious USB device.

Recommendation

Apply the Linux kernel patch that adds a check ensuring the packet size does not exceed maxpacksize, returning -EINVAL if it does.

Other vulnerabilities in Linux kernel

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Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: ALSA: usb-audio: Fix potential overflow of PCM transfer buffer The PCM stream data in USB-audio driver is transferred over USB URB packet buffers, and each packet size is determined dynamically. The packet sizes are limited by some factors such as wMaxPacketSize USB descriptor. OTOH, in the current code, the actually used packet sizes are determined only by the rate and the PPS, which may be bigger than the size limit above. This results in a buffer overflow, as reported by syzbot. Basically when the limit is smaller than the calculated packet size, it implies that something is wrong, most likely a weird USB descriptor. So the best option would be just to return an error at the parameter setup time before doing any further operations. This patch introduces such a sanity check, and returns -EINVAL when the packet size is greater than maxpacksize. The comparison with ep->packsize[1] alone should suffice since it's always equal or greater than ep->packsize[0].

Vulnerability data from NVD (NIST) · CISA KEV · EPSS