CVE-2026-34727 Vikunja ahs a TOTP Two-Factor Authentication Bypass via OIDC Login Path

What is CVE-2026-34727?

CVE-2026-34727 is a high-severity authentication bypass vulnerability in go-vikunja vikunja, published on 10 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Vikunja is an open-source self-hosted task management platform. Prior to 2.3.0, the OIDC callback handler issues a full JWT token without checking whether the matched user has TOTP two-factor authentication enabled. When a local user with TOTP enrolled is matched via the OIDC email fallback mechanism, the second factor is completely skipped. This vulnerability is fixed in 2.3.0.

Weakness: CWE-287

Which versions are affected by CVE-2026-34727?

3 open source packages ship an affected version, including code.vikunja.io/api. It affects 1 product.

Products include Vikunja Vikunja.

How do I fix CVE-2026-34727?

Upgrade code.vikunja.io/api to 2.3.0 or later.

Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.

Is CVE-2026-34727 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-34727 exists.

Other vulnerabilities in go-vikunja vikunja

• CVE-2026-28268 Vikunja Vulnerable to Account Takeover via Password Reset Token Reuse Critical 9.8
• CVE-2026-27575 Vijkunja has Weak Password Policy Combined with Persistent Sessions After Password Change Critical 9.1
• CVE-2026-25935 Vikunja Affected by XSS Via Task Preview High 8.6
• CVE-2026-35595 Vikunja Affected by Privilege Escalation via Project Reparenting High 8.3
• CVE-2026-33316 Vikunja’s Improper Access Control Enables Bypass of Administrator-Imposed Account Disablement High 8.1

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-8jvc-mcx6-r4cg, GO-2026-5258.