Authentication Bypass in Better Auth Library for TypeScript
CVE-2025-61928

9.3CRITICAL

Key Information:

Vendor

Better-auth

Status
Better-auth
Vendor
CVE Published:
9 October 2025

What is CVE-2025-61928?

The Better Auth library for TypeScript contains a serious vulnerability that allows unauthenticated attackers to create and modify API keys for any user. This occurs when attackers manipulate the userId in the request body sent to the API key creation route. The issue arises due to insufficient session checks and faulty field validation, leading to unauthorized access and potential compromise of user data. Users are highly encouraged to update to version 1.3.26 or later to mitigate these risks.

Affected Version(s)

better-auth < 1.3.26

References

https://github.com/better-auth/better-auth/security/advis...
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https://github.com/better-auth/better-auth/commit/5560850...
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CVSS V4

Score:
9.3
Severity:
CRITICAL
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

JSON
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CVE-2025-61928 : Authentication Bypass in Better Auth Library for TypeScript