CVE-2026-62367 Vikunja: OIDC email-fallback account linking ignores email_verified, enabling local-account takeover
Attackers can take over local accounts via OIDC email fallback if enabled, bypassing password checks and email verification.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-62367?
CVE-2026-62367 is a high-severity authentication bypass vulnerability in go-vikunja vikunja, published on 9 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
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.
Which versions are affected by CVE-2026-62367?
3 open source packages ship an affected version, including code.vikunja.io/api.
| Package | Affected | Fixed in |
|---|---|---|
code.vikunja.io/api Go | All versions | None |
code.vikunja.io/api Go | From 1.0.0 | 2.4.0 |
code.vikunja.io/api Go | From 1.0.0 | 2.4.0 |
How do I fix CVE-2026-62367?
Upgrade code.vikunja.io/api to 2.4.0 or later.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-62367 being exploited?
There is no known exploitation of CVE-2026-62367 in the wild and no public exploit code.
Sources
Also known as GHSA-xv7q-fvmc-jx96, GO-2026-6758.