Vikunja before 2.6.0 Authentication Bypass via Unthrottled API
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- High · None · None
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-307.
Summary
Vikunja versions before 2.6.0 fail to apply rate limiting to /api/v2 public authentication endpoints including login, register, password-reset, and OAuth token routes. Remote unauthenticated attackers can perform unbounded credential guessing, account enumeration, and password-reset flooding attacks without throttling restrictions.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| go-vikunja | vikunja | before 2.6.0 | 2.6.0 | Patch available | CNA |
| — | code.vikunja.io/api (Go) | before 2.6.0 | 2.6.0 | Patch available | GHSA-6rvj-qwjf-3m4q |
- vikunja Vendorgo-vikunja Affected before 2.6.0 Fixed in 2.6.0 Patch available CNA
- code.vikunja.io/api (Go) Vendor— Affected before 2.6.0 Fixed in 2.6.0 Patch available GHSA-6rvj-qwjf-3m4q
CPE names Threatist (inferred) · 1
Inferred from how NVD named this product before; not given by a source.
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:vikunja:vikunja:*:*:*:*:*:*:*:* | — | — | go-vikunja |
- cpe:2.3:a:vikunja:vikunja:*:*:*:*:*:*:*:* Versions — — ·go-vikunja
Remediation
- Fix · CNA vikunja (go-vikunja) Fixed in 2.6.0
- Fix · GHSA-6rvj-qwjf-3m4q code.vikunja.io/api (Go) Fixed in 2.6.0 Advisory →
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
go-vikunja vikunja 2.6.0
13 records Highest priority Priority HIGH 3 HIGH, 7 MEDIUM, 3 LOW
Other records, highest priority first
- TI-2026-62115 Vikunja before 2.6.0 Privilege Escalation via Link Share HashPriority HIGH 77
- TI-2026-62108 Vikunja before 2.6.0 Authentication Bypass via CalDAV BasicAuthPriority HIGH 77
- TI-2026-62106 Vikunja before 2.6.0 Denial of Service via Avatar UploadPriority MEDIUM 64
Timeline
- 2026-10-02 Threatist record created from CVE-2026-91972
- 2026-10-03 Alias added: GHSA-m4vj-wr5q-cmvr
- 2026-10-10 Alias added: GHSA-6rvj-qwjf-3m4q
- 2026-10-10 Fix available: Go/code.vikunja.io/[email protected] · GHSA-6rvj-qwjf-3m4q
- 2026-10-10 CVSS score added · GHSA-6rvj-qwjf-3m4q
- 2026-10-10 Weakness changed · GHSA-6rvj-qwjf-3m4q
- 2026-10-10 4 new references · GHSA-6rvj-qwjf-3m4q
- 2026-10-25 EPSS moved to the 50th–90th percentile
References
More go-vikunja vulnerabilities
- TI-2026-40929 Authorization bypass in go-vikunja Vikunja CVSS 4.0CRITICAL 9.3
- TI-2026-21967 Vijkunja has Weak Password Policy Combined with Persistent Sessions After Password Change CVSS 3.1CRITICAL 9.1
- TI-2026-62115 Vikunja before 2.6.0 Privilege Escalation via Link Share Hash CVSS 4.0HIGH 8.7
- TI-2026-62108 Vikunja before 2.6.0 Authentication Bypass via CalDAV BasicAuth CVSS 4.0HIGH 8.7
- TI-2026-26971 Vikunja ahs a TOTP Two-Factor Authentication Bypass via OIDC Login Path CVSS 3.1CRITICAL 9.1
- TI-2026-48322 Vikunja 0.24.0 Broken Object Level Authorization via Link-Share Token CVSS 4.0CRITICAL 9.3
Sources
- CVE-2026-91972 · CVE Program
- CVE-2026-91972 · NVD
- FIRST EPSS
- GHSA-6rvj-qwjf-3m4q · GitHub Advisory Database · CC BY 4.0
- GHSA-m4vj-wr5q-cmvr · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences