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CVE-2026-76216

Status: DeferredHigh (7.7)—

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.

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

Vulnerabilidad de confusión de tipo principal en Vikunja que requiere autenticación (PR:L, JWT válido) en red. El atacante obtiene acceso a datos sensibles (rosters, bots), enumeración (T1552.001) y manipulación de permisos/datos (T1565.001) mediante explotación de colisiones en autoincrement.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

User TrainingRestrict File and Directory PermissionsPrivileged Account ManagementPassword PoliciesApplication Developer GuidanceActive Directory Configuration

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Vikunja — VikunjaAI

CWEs

References

Raw JSON (NVD)

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{
  "id": "CVE-2026-76216",
  "cveTags": [],
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          "options": [
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              "technicalImpact": "total"
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          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
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  "published": "2026-08-19T14:17:47.743",
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  "lastModified": "2026-09-16T20:18:30.540",
  "sourceIdentifier": "disclosure@vulncheck.com"
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