VulnerabilityDeferred

CVE-2026-42565

Prior to 0.5.1, an open redirect vulnerability exists in AuthService.handleCallback due to insufficient validation of the returnPathname value derived from the OAuth state parameter.

MEDIUM 4.3EPSS 0.19%

Does this matter?

Lower severity and a low EPSS score (0.19%). Track it; it rarely justifies an emergency change on its own.

Description

@workos/authkit-session is a toolkit for building WorkOS AuthKit framework integrations. Prior to 0.5.1, an open redirect vulnerability exists in AuthService.handleCallback due to insufficient validation of the returnPathname value derived from the OAuth state parameter. The state parameter is round-tripped through the identity provider (IdP) and can be influenced by an attacker. The handleCallback function decodes and returns returnPathname without enforcing restrictions on origin or scheme. As a result, attacker-controlled values may be returned to the application. If this value is used directly in a redirect, it may cause the user to be redirected to an external, attacker-controlled site. This vulnerability is fixed in 0.5.1.

CVSS 3.1: 4.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
EPSS: 0.19% probability · 9th percentile
CISA KEV: Not listed
Weakness: CWE-601
Source: security-advisories@github.com

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.