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CVE-2026-91983

Vikunja before 2.6.0 API Token Scope Bypass via expand Parameter

Published: Sep 15, 2026Updated: Sep 16, 2026 Sources: CVE List NVDCWE-863

Description

Vikunja before 2.6.0 contains an API token scope bypass vulnerability in task read endpoints where authorization fails to inspect query string parameters. Attackers with limited token scopes can use the expand parameter to access restricted data like comments, reactions, and time entries without proper permission verification.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:LUI:NS:UC:LI:NA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:LConfidentiality
Low
I:NIntegrity
None
A:NAvailability
None

Weaknesses

Affected Products

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques
Initial Access
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References

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