Username enumeration via conditional bcrypt timing
Published Aug 19, 2026 · Updated Aug 25, 2026
Observable timing discrepancy in Wazuh 4.0.0 through 4.14.5 and 5.0.0-beta1 allows remote attackers to enumerate valid usernames. AuthenticationManager.check_user() in framework/wazuh/rbac/orm.py skips check_password_hash() for unknown names but runs costly bcrypt for existing accounts. No credentials or user interaction are required; response-time comparison discloses account validity but not passwords.
Summary
What happened
Observable timing discrepancy in Wazuh 4.0.0 through 4.14.5 and 5.0.0-beta1 allows remote attackers to enumerate valid usernames. AuthenticationManager.check_user() in framework/wazuh/rbac/orm.py skips check_password_hash() for unknown names but runs costly bcrypt for existing accounts. No credentials or user interaction are required; response-time comparison discloses account validity but not passwords.
The record
- CVE
- CVE-2026-44255
- Published
- Aug 19, 2026
- Updated
- Aug 25, 2026
- Vendor
- Wazuh
- Product
- Wazuh
- Classifications
- CWE-208, T1589.001
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 19, 2026CVE publishedPublication date reported by the CVE source.
- Aug 25, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=>= 4.0.0, < 4.14.6
- Affected versionversion=>= 5.0.0-beta1, < 5.0.0-beta2
What conditions does exploitation require?
What is affected?
Published CVSS scores
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.
Weakness, pattern, technique
Public exploit references
- Wazuh authentication timing proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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