CVE-2026-62367: Go-Vikunja Vikunja

High severity, CVSS 7.5. EPSS: 0.1% chance of exploitation in the next 30 days.

Vikunja is an open-source self-hosted task management platform. In versions 1.0.0 through 2.3.0, when an administrator enables the per-provider `emailfallback` option on an OpenID Connect provider, Vikunja links an SSO login to a pre-existing local (username+password) account using only the `email` claim from the IdP. The fallback never checks an `email_verified` (or Microsoft `xms_edov`) signal and never requires the matched account's password. An attacker who can obtain a token from the configured issuer carrying a victim's email logs in as that victim with a full session, with no consent or interaction from the victim. Version 2.4.0 fixes the issue.

Affected products

• Go-Vikunja Vikunja: from 1.0.0, before 2.4.0 (fixed in 2.4.0)

Published 2026-10-09. Last modified 2026-10-09.