CVE-2026-103488 in YouTrack
Summary
by MITRE • 10/01/2026
In JetBrains YouTrack before 2026.2.19422 missing authorisation allowed authenticated users to add themselves to project teams and access restricted issues
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Analysis
by VulDB Data Team • 10/01/2026
The vulnerability identified in versions of JetBrains YouTrack prior to build 2026.2.19422 represents a critical failure in the application's authorization logic, specifically classified under CWE-862 as Missing Authorization. This flaw allows authenticated users who possess valid credentials for the system to bypass intended access controls and elevate their privileges within specific project contexts. The core technical issue stems from an insufficient check on user permissions when processing requests related to team membership modifications. Instead of validating whether the requesting user has administrative rights or explicit permission to modify team rosters, the application accepts these changes based solely on the presence of a valid session token. This design oversight enables any logged-in individual to manipulate internal data structures that define project access levels without triggering appropriate security alerts or requiring additional verification steps from system administrators.
The operational impact of this vulnerability is significant for organizations relying on YouTrack for issue tracking and project management, particularly those with sensitive development workflows or compliance requirements. By exploiting the missing authorization check, an attacker can add themselves to restricted project teams that are typically reserved for senior developers, security engineers, or product managers. Once added to these privileged groups, the user gains access to issues marked as confidential, internal, or otherwise restricted from general view. This unauthorized access compromises the confidentiality of intellectual property, strategic roadmaps, and potentially customer data stored within those tickets. Furthermore, it undermines the integrity of the audit trail, as actions taken by this compromised account appear legitimate because they are performed under a valid user identity, making detection through standard logging mechanisms difficult without deep forensic analysis of permission changes.
From an offensive security perspective, this vulnerability aligns with MITRE ATT&CK technique T1078, specifically Valid Accounts and potentially T1098 if the attacker uses the gained access to further manipulate other system configurations for persistence or lateral movement within the application's ecosystem. The ability to self-add to teams effectively bypasses the principle of least privilege, allowing users to operate with a level of trust that was never granted by the organization’s security policies. This can lead to data exfiltration, sabotage of project timelines through unauthorized modifications to issue statuses or assignments, and potential pivoting into other integrated systems if YouTrack is connected via APIs to tools like CI/CD pipelines or version control repositories where higher privileges might be inferred from team membership.
Mitigation for this vulnerability requires immediate action by upgrading the JetBrains YouTrack instance to version 2026.2.19422 or any later release that includes the security patch addressing these authorization checks. Organizations should also review their current user permissions and audit logs for any suspicious additions of users to restricted teams in the period between when the vulnerability was introduced and its remediation. Implementing stricter access control policies, such as requiring multi-factor authentication for administrative actions or enabling detailed auditing on team membership changes, can provide additional layers of defense against similar authorization flaws in other systems. Regular security assessments and penetration testing focused on role-based access controls are recommended to identify and rectify missing authorization issues before they can be exploited by malicious actors seeking unauthorized access to sensitive project data.