CVE-2026-98837: Linux kernel · ALSA: caiaq: unregister the input device when probe fails
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.3 Medium.
Data as of 28 Oct 2026, 02:27 UTC
CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 18 Oct 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
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix is available that unregisters the input device on the probe error path to prevent use-after-free. Users should update to patched Linux kernel versions that include this fix. No additional mitigation is required beyond applying the official patch.
Description
CVE-2026-98837 is a use-after-free vulnerability in the ALSA caiaq driver in the Linux kernel. The flaw occurs when the input device is registered during probe but not properly unregistered if subsequent initialization steps fail, leading to a dangling pointer. Accessing the input device's "uevent" attribute after this failure causes a kernel memory read of freed memory, triggering a KASAN slab-use-after-free error.
References
- ubuntu.com/security/CVE-2026-98837 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-98837 (opens in a new tab)
- git.kernel.org/stable/c/0b7bd20f6379bc5e431fd74d866390f5b5b63f3c (opens in a new tab)
- git.kernel.org/stable/c/850810c12686f80cdf7530f4f21e0157d904f739 (opens in a new tab)
- git.kernel.org/stable/c/2e5a413cc2a489c9427ecd3d73ad764bfb0c7103 (opens in a new tab)
- git.kernel.org/stable/c/84727facd8506140cd04f2b0a8b1c4ddeac41cea (opens in a new tab)