CVE-2026-74498
Description
In the Linux kernel, the following vulnerability has been resolved: ALSA: usb-audio: Fix DMA buffer out-of-bounds write when fill_max is set When a USB audio endpoint requests full packet transfers via the fill_max descriptor flag, data_ep_set_params() promotes ep->curpacksize to ep->maxpacksize. However, maxsize is left at the original sample-rate derived value. Since u->buffer_size is allocated as maxsize * packets, the resulting DMA buffer is far too small for the requested transfer length. When the USB host controller streams up to curpacksize bytes per packet, it writes past the end of the buffer via DMA, corrupting kernel heap memory. Update maxsize to curpacksize when fill_max is set so that the allocated DMA buffer size matches the actual transfer request size. [ changed to reassign maxsize only when ep->fill_max is set -- tiwai ]
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
Propose a mitigation on Community Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
References
- https://git.kernel.org/stable/c/04595233e5606d452f9f47e6989fc7ae7440fd40
- https://git.kernel.org/stable/c/3852974608f53e530e27c21d0c6c7d79c17b3f5a
- https://git.kernel.org/stable/c/bd65b7191683bebd9923904f0558b9211b9129da
- https://git.kernel.org/stable/c/d0199ae1666ff9ae2d1d568d64c3430d4c47f0e5
- https://git.kernel.org/stable/c/f9b6c9576568169139ac151f7881474f384659fd
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.