CVE-2025-71403

Severity CVSS v4.0:

HIGH

Type:

CWE-601 URL Redirection to Untrusted Site ('Open Redirect')

Publication date:

01/08/2026

Last modified:

01/08/2026

Description

better-auth versions before 1.1.20 contain a bypass vulnerability in trustedOrigins validation logic affecting absolute URLs and wildcard domains. Attackers can construct malicious callbackURL parameters that pass origin checks and trigger open redirects to steal sensitive tokens for account takeover.

Impact

Vector 4.0

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N CVSS v4.0 Severity and Metrics:

Base Score: 7.10 HIGH
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N

Attack Vector (AV): Network
Attack Complexity (AC): Low
Attack Requirements (AT): None
Privileges Required (PR): None
User Interaction (UI): Passsive
Confidentiality (VC): Low
Integrity (VI): High
Availability (VA): None
Confidentiality (SC): None
Integrity (SI): None
Availability (SA): None

Base Score 4.0

7.10

Severity 4.0

HIGH

Vector 3.x

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:N CVSS v3.1 Severity and Metrics:

Base Score: 7.10 HIGH
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:N

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): Required
Scope (S): Unchanged
Confidentiality (C): Low
Integrity (I): High
Availability (A): None

Base Score 3.x

7.10

Severity 3.x

HIGH

CVE-2025-71403

Description

Impact

References to Advisories, Solutions, and Tools