CVE-2025-40269

ALSA: usb-audio: Fix potential overflow of PCM transfer buffer

At a glance

Severity
HIGH 7.8
EPSS
EPSS 0.18 % · percentile 7 (2026-10-27)
State
PUBLISHED
Published
Updated
Assigner
Linux
NVD status
Deferred

Description

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].

Scores

VersionScoreVectorScored by
CVSS 3.1HIGH 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HLinux
CVSS 3.1HIGH 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HNVD · 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Secondary)

European references

CERT-FR advisories

Affected products

ProductVersions
Linux · Linuxaffected 02c56650f3c118d3752122996d96173d26bb13aa < 480a1490c595a242f27493a4544b3efb21b29f6a ; affected 5ef30e443e6d3654cccecec99cf481a69a0a6d3b < ab0b5e92fc36ee82c1bd01fe896d0f775ed5de41 ; affected 99703c921864a318e3e8aae74fde071b1ff35bea < 282aba56713bbc58155716b55ca7222b2d9cf3c8 ; affected 2d50acd7dbd0682a56968ad9551341d7fc5b6eaf < c4dc012b027c9eb101583011089dea14d744e314 ; affected aba41867dd66939d336fdf604e4d73b805d8039f < e0ed5a36fb3ab9e7b9ee45cd17f09f6d5f594360 ; affected d288dc74f8cf95cb7ae0aaf245b7128627a49bf3 < d67dde02049e632ba58d3c44a164a74b6a737154
Linux · Linuxaffected 5.8 ; unaffected 0 < 5.8 ; unaffected 4.4.230 ≤ 4.4.* ; unaffected 4.9.230 ≤ 4.9.* ; unaffected 4.14.188 ≤ 4.14.* ; unaffected 4.19.132 ≤ 4.19.*

References

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD