Username enumeration via BasicAuth timing oracle
Published Jul 8, 2026 · Updated Jul 8, 2026
Information disclosure in GoFiber Fiber before 3.3.0 allows remote attackers to enumerate BasicAuth usernames through response timing. The default Authorizer in middleware/basicauth/config.go short-circuits after a failed username lookup, skipping the password-hash comparison performed for existing users. Exploitation requires an application to use BasicAuth's default Authorizer with hashed passwords; the disclosed result is valid-account discovery, not authentication bypass.
Summary
What happened
Information disclosure in GoFiber Fiber before 3.3.0 allows remote attackers to enumerate BasicAuth usernames through response timing. The default Authorizer in middleware/basicauth/config.go short-circuits after a failed username lookup, skipping the password-hash comparison performed for existing users. Exploitation requires an application to use BasicAuth's default Authorizer with hashed passwords; the disclosed result is valid-account discovery, not authentication bypass.
The record
- CVE
- CVE-2026-44332
- Published
- Jul 8, 2026
- Updated
- Jul 8, 2026
- Vendor
- GoFiber
- Product
- Fiber
- Classifications
- CWE-203, T1087
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 8, 2026CVE publishedPublication date reported by the CVE source.
- Jul 8, 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?
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- Affected versionversion=< 3.3.0
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
- BasicAuth timing-oracle proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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