CVE-2026-58440 in Gitea
Summary
by MITRE • 08/13/2026
Webhooks created by a collaborator keep firing after their repo access is revoked → ongoing real-time exfiltration of private repo content (incomplete revocation cleanup in `DeleteCollaboration`)
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Analysis
by VulDB Data Team • 08/13/2026
This vulnerability represents a critical access control flaw in repository management systems where webhooks associated with collaborators continue to function even after their repository access has been revoked. The root cause lies in the incomplete cleanup process within the DeleteCollaboration function which fails to properly terminate or remove webhook configurations tied to the revoked user's permissions. This creates a persistent security risk where malicious actors can maintain unauthorized real-time data exfiltration channels from private repositories.
The technical implementation of this vulnerability stems from improper resource management during collaboration removal operations. When a collaborator is removed from a repository, the system should ensure complete cleanup of all associated webhook endpoints, API tokens, and permission configurations. However, the current implementation only processes direct access revocation without accounting for indirect system components that may have been granted access through the collaboration relationship. This oversight creates a persistent attack surface where webhooks can continue firing indefinitely, potentially exposing sensitive code repositories, configuration files, and private data to unauthorized parties.
The operational impact of this vulnerability extends far beyond simple permission mismanagement, creating significant risk for organizations relying on collaborative development environments. Attackers who gain initial access through legitimate collaboration relationships can maintain persistent access even after being removed from the system, enabling continuous monitoring and data extraction from private repositories. This scenario directly violates the principle of least privilege and demonstrates a failure in proper access lifecycle management. The real-time nature of webhook functionality means that data exfiltration occurs immediately upon any repository changes rather than requiring additional attack vectors or delayed exploitation techniques.
Organizations should implement comprehensive access revocation procedures that include webhook cleanup as part of their collaboration removal processes. The vulnerability aligns with CWE-284 Access Control Issues and demonstrates characteristics consistent with ATT&CK technique T1078 Valid Accounts, where adversaries maintain access through compromised legitimate credentials or permissions. Mitigation strategies should focus on implementing automated cleanup routines that verify all associated webhook endpoints are properly terminated when collaborations are removed, along with regular auditing of active webhook configurations to ensure no orphaned connections persist after access revocation. Additionally, organizations should implement monitoring solutions that can detect unauthorized webhook activity and establish clear protocols for immediate notification and remediation when such anomalies occur.
The persistence of this vulnerability highlights the importance of proper resource lifecycle management in security-critical systems and demonstrates how seemingly minor implementation gaps can create significant long-term risks. Organizations must ensure that their access control systems properly account for all indirect dependencies and associated resources when implementing permission revocation operations, particularly in environments where real-time data synchronization through webhooks is common practice.