CVE-2023-0266 — Linux Kernel Use-After-Free Vulnerability

A use after free vulnerability exists in the ALSA PCM package in the Linux Kernel. SNDRV_CTL_IOCTL_ELEM_{READ|WRITE}32 is missing locks that can be used in a use-after-free that can result in a priviledge escalation to gain ring0 access from the system user. We recommend upgradin

01What is this vulnerability?

A use after free vulnerability exists in the ALSA PCM package in the Linux Kernel. SNDRV_CTL_IOCTL_ELEM_{READ|WRITE}32 is missing locks that can be used in a use-after-free that can result in a priviledge escalation to gain ring0 access from the system user. We recommend upgrading past commit 56b88b50565cd8b946a2d00b0c83927b7ebb055e

02Affected products

Vendor	Product	Versions
Linux	Linux Kernel	4.14

03Active exploitation status

Yes — actively exploited. Added to the CISA KEV catalog on 2023-03-30. Ransomware use: Unknown.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Open the Sigma generator with a pre-filled prompt for this CVE to draft a starting detection in your stack of choice:

Open in Sigma generator →

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2023-01-30T13:09:32.141Z
• Last modified: 2025-10-21T23:15:27.844Z
• Added to CISA KEV: 2023-03-30
• BOD 22-01 due: 2023-04-20

09References

• github.com — https://github.com/torvalds/linux/commit/becf9e5d553c2389d857a3c178ce80fdb34a02e…
• git.kernel.org — https://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git/tree/que…
• github.com — https://github.com/torvalds/linux/commit/56b88b50565cd8b946a2d00b0c83927b7ebb055…
• lists.debian.org — https://lists.debian.org/debian-lts-announce/2023/05/msg00006.html