Unauthenticated account creation via missing registration enforcement
Published Aug 19, 2026 · Updated Aug 19, 2026
Authentication bypass in PoxenStudio MyBooks 3.41.2 and earlier allows remote attackers to create accounts despite disabled registration. The SignUp.post handler for POST /api/user/sign_up processes account data without checking ALLOW_REGISTER, while process_auth_header accepts the new account without checking its active flag. Exploitation requires network access to an instance with public registration disabled and grants immediate user-level API access under attacker-chosen credentials.
Summary
What happened
Authentication bypass in PoxenStudio MyBooks 3.41.2 and earlier allows remote attackers to create accounts despite disabled registration. The SignUp.post handler for POST /api/user/sign_up processes account data without checking ALLOW_REGISTER, while process_auth_header accepts the new account without checking its active flag. Exploitation requires network access to an instance with public registration disabled and grants immediate user-level API access under attacker-chosen credentials.
The record
- CVE
- CVE-2026-45274
- Published
- Aug 19, 2026
- Updated
- Aug 19, 2026
- Vendor
- PoxenStudio
- Product
- MyBooks
- Classifications
- CWE-602, T1136
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 19, 2026CVE publishedPublication date reported by the CVE source.
- Aug 19, 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=< 3.42.0
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
- Talebook registration-bypass proof of conceptproof of concept · demonstrated
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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