CVE-2025-54336Public exploitNetwork attack vector

Administrator login bypass via loose password comparison

Published Aug 19, 2025 · Updated Aug 29, 2025

Authentication bypass in Plesk Obsidian 18.0.70 allows remote attackers to obtain administrator access through the login interface. _isAdminPasswordValid in admin/plib/LoginManager.php uses PHP's loose == operator to compare supplied input with the decrypted administrator password. Full login bypass requires the stored password to match 0e followed only by digits; otherwise, the comparison improves brute-force attacks through timing or type confusion.

CVSS severity9.8
Critical
EPSS probability0.51%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authentication bypass in Plesk Obsidian 18.0.70 allows remote attackers to obtain administrator access through the login interface. _isAdminPasswordValid in admin/plib/LoginManager.php uses PHP's loose == operator to compare supplied input with the decrypted administrator password. Full login bypass requires the stored password to match 0e followed only by digits; otherwise, the comparison improves brute-force attacks through timing or type confusion.

The record

CVE
CVE-2025-54336
Published
Aug 19, 2025
Updated
Aug 29, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-697, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 19, 2025CVE publishedPublication date reported by the CVE source.
  2. Aug 29, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

9.8GitHub Advisory DatabaseCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-697Incorrect Comparison
T1190Exploit Public-Facing Application

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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