9.1

CVE-2026-34727: go-vikunja vikunja Improper Authentication

CVSS: 9.1v3.1CriticalAnalyzed
AliasesGHSA-8jvc-mcx6-r4cgGO-2026-5258
Published 10-04-2026Last modified 13-04-2026
Open JSON

Vulnerability summary

CVE-2026-34727 is a critical (CVSS 9.1) Improper Authentication vulnerability in go-vikunja vikunja. EPSS estimates a 0.42% chance of exploitation in the next 30 days, higher than 34.9% of scored vulnerabilities. 1 public exploit is recorded.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.1/10
010
Critical · v3.1 (NVD)
EPSS score
0.42%
0%100%
Low · +0.14 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1github

Advisory lineage

Upstream 0 · Downstream 1 · Related 1
OPENSUSE-SU-2026:21483-1

Timeline

  1. 10-04-2026
    PublishedVulnerability first disclosed.
  2. 13-04-2026
    Last modifiedVulnerability information updated.

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.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.42%

Chance of exploitation in the next 30 days

Percentile

35%

Versus all other CVEs

30-day change

+0.14 pp

From 0.28% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.42%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

1 found
  • githubUnverified

    Vikunja

    Maturity: poc

Weaknesses

CWE · root cause

Affected systems

Code.vikunja.io1 product
  • api< 2.3.0 | All versions (No fix recorded)
Go-vikunja1 product
Vikunja1 product

3 vendors · 3 products

References

6 links