CVE-2025-59538: Argo CD is Vulnerable to Unauthenticated Remote DoS via malformed Azure DevOps git.push webhook

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 9.4% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2025-10-01 · updated 2026-10-12
Weakness: CWE-248

Description

Argo CD is a declarative, GitOps continuous delivery tool for Kubernetes. For versions 2.9.0-rc1 through 2.14.19, 3.0.0-rc1 through 3.2.0-rc1, 3.1.6 and 3.0.17, when the webhook.azuredevops.username and webhook.azuredevops.password are not set in the default configuration, the /api/webhook endpoint crashes the entire argocd-server process when it receives an Azure DevOps Push event whose JSON array resource.refUpdates is empty. The slice index [0] is accessed without a length check, causing an index-out-of-range panic. A single unauthenticated HTTP POST is enough to kill the process. This issue is resolved in versions 2.14.20, 3.2.0-rc2, 3.1.8 and 3.0.19.

Affected products

argoproj argo-cd: from 2.9.0 before 2.14.20; from 3.0.0 before 3.0.19; from 3.1.0 before 3.1.8; 3.2.0-rc1 — fixed in 2.14.20, 3.0.19, 3.1.8

How to fix

Upgrade to a fixed version: argoproj argo-cd 2.14.20, 3.0.19, 3.1.8. Check the vendor advisory for mitigations.

References

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