Unauthenticated account takeover via unlimited OTP guesses
Published May 21, 2025 · Updated Aug 27, 2025
Authentication bypass in UnitedOver Digits before 8.4.6.1 allows remote attackers to take over accounts via OTP brute force. The OTP validation flow accepts repeated guesses without rate limiting, allowing the finite verification code to be enumerated. No authentication or user interaction is required; a correct guess grants access to the targeted account, including an administrator account.
Summary
What happened
Authentication bypass in UnitedOver Digits before 8.4.6.1 allows remote attackers to take over accounts via OTP brute force. The OTP validation flow accepts repeated guesses without rate limiting, allowing the finite verification code to be enumerated. No authentication or user interaction is required; a correct guess grants access to the targeted account, including an administrator account.
The record
- CVE
- CVE-2025-4094
- Published
- May 21, 2025
- Updated
- Aug 27, 2025
- Vendor
- UnitedOver
- Product
- Digits
- Classifications
- CWE-307, T1110
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 21, 2025CVE publishedPublication date reported by the CVE source.
- Aug 27, 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?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0 <8.4.6.1
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
- CVE-2025-4094 Digits OTP authentication-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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