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TI-2026-27700 Aliases CVE-2026-35597GHSA-fgfv-pv97-6cmj

Vikunja Affected by TOTP Brute-Force Due to Non-Functional Account Lockout

Priority HIGH 66CWE-307Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · None · None
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub. Impact type from CWE-307.

Summary

Vikunja is an open-source self-hosted task management platform. Prior to 2.3.0, the TOTP failed-attempt lockout mechanism is non-functional due to a database transaction handling bug. When a TOTP validation fails, the login handler in pkg/routes/api/v1/login.go calls HandleFailedTOTPAuth and then unconditionally rolls back. HandleFailedTOTPAuth in pkg/user/totp.go uses an in-memory counter (key-value store) to track failed attempts. When the counter reaches 10, it calls user.SetStatus(s, StatusAccountLocked) on the same database session s. Because the login handler always rolls back after a TOTP failure, the StatusAccountLocked write is undone. The in-memory counter correctly increments past 10, so the lockout code executes on every subsequent attempt, but the database write is rolled back every time. This allows unlimited brute-force attempts against TOTP codes. This vulnerability is fixed in 2.3.0.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00308 23rd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed vikunja (go-vikunja): 2.3.0code.vikunja.io/api (Go): 2.3.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
go-vikunjavikunjabefore 2.3.02.3.0Patch availableCNA
—code.vikunja.io/api (Go)before 2.3.02.3.0Patch availableGHSA-fgfv-pv97-6cmj
  • vikunja Vendorgo-vikunja Affected before 2.3.0 Fixed in 2.3.0 Patch available CNA
  • code.vikunja.io/api (Go) Vendor— Affected before 2.3.0 Fixed in 2.3.0 Patch available GHSA-fgfv-pv97-6cmj

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:vikunja:vikunja:*:*:*:*:*:*:*:*before 2.3.0Vulnerablego-vikunja
  • cpe:2.3:a:vikunja:vikunja:*:*:*:*:*:*:*:* Versions before 2.3.0 Vulnerable ·go-vikunja

Remediation

  • Fix · CNA vikunja (go-vikunja) Fixed in 2.3.0
  • Fix · GHSA-fgfv-pv97-6cmj code.vikunja.io/api (Go) Fixed in 2.3.0 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-35597
  2. 2026-10-03 Alias added: GHSA-fgfv-pv97-6cmj

References

  • TI-2026-21967 Vijkunja has Weak Password Policy Combined with Persistent Sessions After Password Change CVSS 3.1CRITICAL 9.1
  • TI-2026-26971 Vikunja ahs a TOTP Two-Factor Authentication Bypass via OIDC Login Path CVSS 3.1CRITICAL 9.1
  • TI-2026-26060 Vikunja Vulnerable to Link Share Hash Disclosure via ReadAll Endpoint Enables Permission Escalation CVSS 3.1HIGH 7.5
  • TI-2026-20965 Vikunja Affected by XSS Via Task Preview CVSS 4.0HIGH 8.6
  • TI-2026-27698 Vikunja Affected by Privilege Escalation via Project Reparenting CVSS 3.1HIGH 8.3
  • TI-2026-25727 Vikunja’s Improper Access Control Enables Bypass of Administrator-Imposed Account Disablement CVSS 3.1HIGH 8.1
See all 34 →

Sources