CVE-2025-55191 is a medium-severity race condition vulnerability affecting multiple versions of Argo CD, a popular GitOps continuous delivery tool for Kubernetes environments. The flaw exists in the repository credentials handler, specifically within the util/db/repository_secrets.go file, where improper synchronization allows concurrent operations on the same repository URL to cause a race condition. When exploited, this race condition leads to the Argo CD server panicking and crashing, resulting in denial of service (DoS). To trigger this vulnerability, an attacker must possess a valid API token with repository resource permissions that allow create, update, or delete actions. No user interaction is required beyond possessing these permissions. The vulnerability affects versions from 2.1.0 up to but not including 2.14.20, as well as certain release candidate versions in the 3.x series. The issue has been resolved in versions 2.14.20, 3.2.0-rc2, 3.1.8, and 3.0.19. The CVSS v3.1 score is 6.5, reflecting a medium severity with network attack vector, low attack complexity, requiring privileges but no user interaction, and impacting availability only. There are no known exploits in the wild at this time. The vulnerability can be repeatedly triggered to maintain persistent denial of service, disrupting all GitOps operations managed by Argo CD, which can severely impact continuous delivery pipelines and Kubernetes cluster management.

For European organizations relying on Argo CD for Kubernetes continuous delivery, this vulnerability poses a significant risk to operational continuity. Successful exploitation results in the Argo CD server crashing, causing disruption or complete halt of GitOps workflows. This can delay application deployments, updates, and rollback procedures, potentially impacting business-critical services. Organizations with automated deployment pipelines that depend on Argo CD may experience downtime or degraded service levels. Given the requirement for a valid API token with repository permissions, insider threats or compromised credentials could be leveraged to exploit this vulnerability. The impact is primarily on availability, but the resulting operational disruption can indirectly affect integrity and confidentiality if deployment processes are interrupted or altered. The medium severity rating aligns with the need for privileges to exploit, but the ease of triggering repeated crashes elevates the risk of sustained denial of service. European entities in sectors such as finance, healthcare, and critical infrastructure that use Kubernetes and GitOps practices are particularly vulnerable to operational disruptions caused by this flaw.

1. Immediate upgrade to patched versions of Argo CD: 2.14.20 or later, 3.2.0-rc2, 3.1.8, or 3.0.19 as applicable. 2. Restrict API token permissions strictly to the minimum necessary, especially limiting repository resource create, update, and delete actions to trusted personnel and automated systems. 3. Implement robust monitoring and alerting on Argo CD server health and logs to detect repeated crashes or panics indicative of exploitation attempts. 4. Employ network segmentation and access controls to limit exposure of the Argo CD API endpoints to only authorized users and systems. 5. Regularly audit API tokens and rotate credentials to reduce risk from compromised tokens. 6. Consider implementing rate limiting or throttling on repository operations to reduce the likelihood of rapid repeated triggering of the race condition. 7. Conduct internal penetration testing and code reviews focusing on concurrency and synchronization issues in custom extensions or integrations with Argo CD. 8. Maintain an incident response plan tailored to Kubernetes and GitOps environments to quickly recover from potential denial-of-service events.