# CVE-2023-0266: Linux Kernel Use-After-Free Vulnerability

Source: https://junglewise.ai/threats/cve-2023-0266-linux-kernel-use-after-free-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2023-03-30. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2023-0266 · Severity: critical · CVSS 7.9 · Exploited in the wild · Published 2023-03-30

A use-after-free vulnerability in the ALSA PCM package of the Linux Kernel occurs due to missing locks in SNDRV_CTL_IOCTL_ELEM_READ/WRITE32. This flaw allows a local system user to escalate privileges to ring0 access.

Technologies: [Linux Kernel](https://junglewise.ai/threats/technologies/kernel). Vendors: [Linux](https://junglewise.ai/threats/vendors/linux).

## Quick answers

**Is CVE-2023-0266 exploited in the wild?** Yes. CVE-2023-0266 is known to be exploited in the wild, first recorded on 30 March 2023. Treat it as urgent.

**How severe is CVE-2023-0266?** Critical severity, with a CVSS score of 7.9, published 30 March 2023.

**Which products and versions are affected?** Linux Linux Kernel up to (excluding) 6.2, 6.2 rc1; Debian Debian Linux 10.0.

**Is there a fix for CVE-2023-0266?** A patch was published on 2023-01-12: Mainline kernel commit 56b88b50565cd8b946a2d00b0c83927b7ebb055e Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2023-0266 attacked?** It is attacked with local access, in an operating system.

**Am I affected by CVE-2023-0266?** Check whether you run Linux Kernel. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Affected products

- Linux Linux Kernel up to (excluding) 6.2, 6.2 rc1
- Debian Debian Linux 10.0

## Timeline

- 2023-03-30: disclosed
- 2023-03-30: kev added: Added to CISA Known Exploited Vulnerabilities Catalog
- 2023-03-30: advisory
- 2023-01-12: patched: Mainline kernel commit 56b88b50565cd8b946a2d00b0c83927b7ebb055e

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