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TI-2026-53321 Aliases CVE-2026-76216GHSA-32r8-5843-4qw2GHSA-9xwc-vwww-qqmw

Vikunja through 2.4.0 Principal-Type Confusion via LinkSharing

Priority LOW 36CWE-639Published · Updated

Key facts

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

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-639, CWE-843 and the CVSS impact.

Summary

Vikunja through 2.4.0 contains a principal-type confusion vulnerability where LinkSharing principals with id N are treated as user principals with users.id == N at three permission checks lacking type guards. Attackers with a link-share JWT can remove victims from teams, enumerate and delete victim bot users, or read team rosters by exploiting id collisions in the autoincrement space.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00363 30th percentileScored 2026-11-07
Fix Fixed code.vikunja.io/api (Go): 2.5.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

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-vikunjavikunjaup to 2.4.0—No fix listedCNA
—code.vikunja.io/api (Go)before 2.5.02.5.0Patch availableGHSA-32r8-5843-4qw2
  • vikunja Vendorgo-vikunja Affected up to 2.4.0 Fixed in — No fix listed CNA
  • code.vikunja.io/api (Go) Vendor— Affected before 2.5.0 Fixed in 2.5.0 Patch available GHSA-32r8-5843-4qw2

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:vikunja:vikunja:*:*:*:*:*:*:*:*——go-vikunja
  • cpe:2.3:a:vikunja:vikunja:*:*:*:*:*:*:*:* Versions — — ·go-vikunja

Remediation

  • Fix · GHSA-32r8-5843-4qw2 code.vikunja.io/api (Go) Fixed in 2.5.0 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-76216
  2. 2026-10-03 Alias added: GHSA-9xwc-vwww-qqmw
  3. 2026-10-10 Alias added: GHSA-32r8-5843-4qw2
  4. 2026-10-10 Affected versions changed · GHSA-32r8-5843-4qw2
  5. 2026-10-10 CVSS score added · GHSA-32r8-5843-4qw2
  6. 2026-10-10 Weakness changed · GHSA-32r8-5843-4qw2
  7. 2026-10-10 3 new references · GHSA-32r8-5843-4qw2

References

Advisory 2

Other 3

  • 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-2026-62107 Vikunja before 2.6.0 Authentication Bypass via Unthrottled API 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
See all 105 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences