CVE-2026-105447 in Quay
Summary
by MITRE • 10/06/2026
A flaw was found in Quay. When handling build trigger requests, the application incorrectly exposes trigger configuration details containing repository write tokens to global read-only administrative users. An authenticated user with read-only privileges can exploit this flaw by querying the build trigger API to retrieve these delegate tokens. This issue allows a restricted user to bypass read-only limitations and push arbitrary container images to private repositories, leading to privilege escalation.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 10/06/2026
The vulnerability identified in Quay represents a critical authorization failure within the application's build trigger subsystem, specifically affecting users with global read-only administrative privileges. In secure software architecture, the principle of least privilege dictates that users should be granted only the minimum levels of access necessary to perform their job functions. However, this flaw allows an authenticated user who is explicitly restricted from writing or modifying repository content to bypass these constraints by interacting with the build trigger API endpoints. The core technical issue lies in insufficient access control checks during the retrieval of configuration details for build triggers. When a read-only administrator queries these endpoints, the application incorrectly includes sensitive delegate tokens associated with repository write permissions within the response payload. This misconfiguration effectively leaks credentials that should be strictly confined to users or services possessing write-level authorization, thereby undermining the integrity of the access control model implemented by the organization.
From an operational perspective, this vulnerability enables a significant privilege escalation attack vector. An attacker who has obtained read-only administrative rights can exploit this flaw to extract repository write tokens without needing higher-level credentials such as passwords or multi-factor authentication factors associated with admin accounts. Once these delegate tokens are acquired, they can be used directly against the container registry API to push arbitrary container images into private repositories that were previously inaccessible to the attacker. This capability allows for the injection of malicious code, backdoors, or compromised software artifacts into critical supply chain pipelines. The impact extends beyond simple data exfiltration; it compromises the integrity of the entire deployment pipeline, as downstream systems may automatically pull and execute these tainted images, potentially leading to widespread compromise of production environments dependent on those repositories.
This flaw aligns with CWE-269, which describes Improper Privilege Assignment, where a user is granted privileges that exceed their intended role or clearance level. Furthermore, the exploitation technique maps directly to MITRE ATT&CK tactic T1078, specifically Valid Accounts and potentially T1534 if used for lateral movement within container orchestration platforms like Kubernetes. The ability to push images using stolen tokens also relates to CWE-269 as it involves gaining unauthorized access to a resource through misconfigured permissions rather than exploiting a buffer overflow or injection flaw. The severity is heightened by the fact that read-only administrators are often trusted with high-level visibility into system configurations, making them attractive targets for attackers who have already compromised an account but lack write privileges.
Mitigation strategies must focus on both immediate remediation and long-term architectural improvements. Quay maintainers should release a patch that enforces strict access control checks when generating or returning build trigger configuration data, ensuring that sensitive tokens are never included in responses to users lacking explicit write permissions for the associated repositories. Administrators running vulnerable versions of Quay should immediately rotate all repository delegate tokens and review audit logs for any unauthorized API calls originating from read-only accounts. To prevent recurrence, organizations should implement rigorous code reviews focusing on authorization logic, particularly around API endpoints that handle sensitive configuration data. Additionally, adopting a zero-trust security model where every request is verified against current permissions regardless of the user's initial role can help mitigate similar flaws in other components of the infrastructure. Regular penetration testing and vulnerability scanning focused on access control mechanisms are essential to identify such privilege escalation paths before they can be exploited by malicious actors.