CVE-2026-121802
Published:November 04, 2026
Updated:November 05, 2026
@better-auth/expo before 1.7.16 allows certain account-takeover outcomes (e.g., unauthenticated changes of any account's email address), because it signs a caller-supplied state value without checking whether that value had been issued by the server. NOTE: the application secret must be rotated after updating to a fixed version.
Affected Packages
https://github.com/better-auth/better-auth.git (GITHUB):
Affected version(s) >=v1.8.0-beta.0 <v1.8.0-beta.5Fix Suggestion:
Update to version v1.8.0-beta.5https://github.com/better-auth/better-auth.git (GITHUB):
Affected version(s) >=v0.7.4-beta.1 <v1.7.16 || >=v1.0.0 <v1.7.16Fix Suggestion:
Update to version v1.7.16@better-auth/expo (NPM):
Affected version(s) >=1.8.0-beta.0 <1.8.0-beta.5Fix Suggestion:
Update to version 1.8.0-beta.5@better-auth/expo (NPM):
Affected version(s) >=1.4.0 <1.7.16 || >=1.4.0-beta.6 <1.7.16Fix Suggestion:
Update to version 1.7.16better-auth (NPM):
Affected version(s) >=1.8.0-beta.0 <1.8.0-beta.5Fix Suggestion:
Update to version 1.8.0-beta.5better-auth (NPM):
Affected version(s) >=0.7.4-beta.1 <1.7.16 || >=1.0.0 <1.7.16Fix Suggestion:
Update to version 1.7.16Related Resources (5)
Do you need more information?
Contact UsCVSS v4
Base Score:
9.3
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
HIGH
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
9.1
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Weakness Type (CWE)
Origin Validation Error
EPSS
Base Score:
0.20