ALSA: ua101: reject mismatched capture/playback packet sizes
In the Linux kernel, the following vulnerability has been resolved: ALSA: ua101: reject mismatched capture/playback packet sizes detect_usb_format() cross-checks bSubframeSize, bBitResolution and tSamFreq between the capture and playback interfaces, but never relates the two endpoints' wMaxPacketSize and bNrChannels. Each playback URB gets a buffer of ua->playback.max_packet_bytes, while the number of bytes written into it is derived from the capture stream: capture_urb_complete() computes frames from the received capture packet and capture.frame_bytes, and start_usb_playback() and playback_work() multiply that by playback.frame_bytes. A device declaring a large capture wMaxPacketSize with few capture channels and a small playback wMaxPacketSize with many playback channels therefore memset()s and memcpy()s past the end of the playback buffer, in open() of the PCM node the driver registers during probe. usb_submit_urb() rejects the over-long iso_frame_desc[0].length with -EMSGSIZE, but only after the write. Reject such descriptors at probe time. Genuine UA-101/UA-1000 hardware declares proportional packet sizes and is unaffected. BUG: KASAN: slab-out-of-bounds in start_usb_playback (sound/usb/misc/ua101.c:586) Write of size 2048 at addr ffff8881098f3c00 by task exploit/5021 Call Trace: __asan_memset (mm/kasan/shadow.c:84) start_usb_playback (sound/usb/misc/ua101.c:586) playback_pcm_open (sound/usb/misc/ua101.c:679) snd_pcm_open_substream (sound/core/pcm_native.c:2829) snd_pcm_
CVE-2026-98741
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-98741
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "63978ab3e3e963db28093b53bb4598f2702e1ad7",
"lessThan": "ada5ded765f059a6e3036e69ca350449442af0fc",
"versionType": "git"
},
{
"status": "affected",
"version": "63978ab3e3e963db28093b53bb4598f2702e1ad7",
"lessThan": "fd3a7bf0d988b0878a1957df150edb35f81db87e",
"versionType": "git"
},
{
"status": "affected",
"version": "63978ab3e3e963db28093b53bb4598f2702e1ad7",
"lessThan": "eb0c7fda59cf650076f8ed5b949a6c8441aa3606",
"versionType": "git"
},
{
"status": "affected",
"version": "63978ab3e3e963db28093b53bb4598f2702e1ad7",
"lessThan": "4294fe57048594a9e158b61c967bb7f943cda477",
"versionType": "git"
},
{
"status": "affected",
"version": "63978ab3e3e963db28093b53bb4598f2702e1ad7",
"lessThan": "86f86e6fdedc33c5b8d38b9208b350f8accf57ee",
"versionType": "git"
}
],
"programFiles": [
"sound/usb/misc/ua101.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "2.6.34"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "2.6.34",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.6.160",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.113",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.56",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.10",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"sound/usb/misc/ua101.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-98741
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #48939 · Revision 1
- Added to Heist Feed
- Publisher date