Administrative takeover via unauthenticated passkey registration
Published Jun 17, 2026 · Updated Jun 17, 2026
Authentication bypass in Hermes WebUI before 0.51.409 allows remote attackers to gain administrative control through passkey registration. The registration-options and registration handlers accept unauthenticated requests when no credential exists, allowing the requester to bind an attacker-controlled passkey as the first credential. The path requires passkeys to be enabled and no existing credential; successful enrollment establishes persistent administrative access.
Summary
What happened
Authentication bypass in Hermes WebUI before 0.51.409 allows remote attackers to gain administrative control through passkey registration. The registration-options and registration handlers accept unauthenticated requests when no credential exists, allowing the requester to bind an attacker-controlled passkey as the first credential. The path requires passkeys to be enabled and no existing credential; successful enrollment establishes persistent administrative access.
The record
- CVE
- CVE-2026-55196
- Published
- Jun 17, 2026
- Updated
- Jun 17, 2026
- Vendor
- Nathan Esquenazi
- Product
- Hermes WebUI
- Classifications
- T1098
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 17, 2026CVE publishedPublication date reported by the CVE source.
- Jun 17, 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=0 <0.51.409
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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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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