CVE-2026-23208: Linux kernel · ALSA: usb-audio: Prevent excessive number of frames
Affects Linux kernelSource CVE Database V5
Not known to be exploited · fixed in ef5749ef8b307bf8717945701b1b79d036af0a15 : update Linux kernel when convenient.
Data as of 26 Oct 2026, 14:18 UTC
Rated by Threat Radar · No CVSS score from NVD or the CNA
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 8% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in ef5749ef8b307bf8717945701b1b79d036af0a15, e0ed5a36fb3ab9e7b9ee45cd17f09f6d5f594360, d67dde02049e632ba58d3c44a164a74b6a737154 +13
Exploitation evidence
Disclosed: evidence found.
CVE published 14 Feb 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in– |
Description
In the Linux kernel, the following vulnerability has been resolved: ALSA: usb-audio: Prevent excessive number of frames In this case, the user constructed the parameters with maxpacksize 40 for rate 22050 / pps 1000, and packsize[0] 22 packsize[1] 23. The buffer size for each data URB is maxpacksize * packets, which in this example is 40 * 6 = 240; When the user performs a write operation to send audio data into the ALSA PCM playback stream, the calculated number of frames is packsize[0] * packets = 264, which exceeds the allocated URB buffer size, triggering the out-of-bounds (OOB) issue reported by syzbot [1]. Added a check for the number of single data URB frames when calculating the number of frames to prevent [1]. [1] BUG: KASAN: slab-out-of-bounds in copy_to_urb+0x261/0x460 sound/usb/pcm.c:1487 Write of size 264 at addr ffff88804337e800 by task syz.0.17/5506 Call Trace: copy_to_urb+0x261/0x460 sound/usb/pcm.c:1487 prepare_playback_urb+0x953/0x13d0 sound/usb/pcm.c:1611 prepare_outbound_urb+0x377/0xc50 sound/usb/endpoint.c:333
References
- git.kernel.org/stable/c/480a1490c595a242f27493a4544b3efb21b29f6a (opens in a new tab)
- git.kernel.org/stable/c/ab0b5e92fc36ee82c1bd01fe896d0f775ed5de41 (opens in a new tab)
- git.kernel.org/stable/c/282aba56713bbc58155716b55ca7222b2d9cf3c8 (opens in a new tab)
- git.kernel.org/stable/c/c4dc012b027c9eb101583011089dea14d744e314 (opens in a new tab)
- git.kernel.org/stable/c/e0ed5a36fb3ab9e7b9ee45cd17f09f6d5f594360 (opens in a new tab)
- git.kernel.org/stable/c/d67dde02049e632ba58d3c44a164a74b6a737154 (opens in a new tab)
- git.kernel.org/stable/c/152fc4f7b4a8af1c0418d2722f3b2729799cc837 (opens in a new tab)
- git.kernel.org/stable/c/81e4b0009f2acc841d77a24fd796528b0bf62c4e (opens in a new tab)
- git.kernel.org/stable/c/62932d9ed639a9fa71b4ac1a56766a4b43abb7e4 (opens in a new tab)
- git.kernel.org/stable/c/ef5749ef8b307bf8717945701b1b79d036af0a15 (opens in a new tab)