CVE-2025-59538
HIGHCVE-2025-59538 is a high-severity (CVSS 7.5) CWE-248 vulnerability in github.com/argoproj/argo-cd/v2. O3 Security confirms whether CVE-2025-59538 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Argo CD is Vulnerable to Unauthenticated Remote DoS via malformed Azure DevOps git.push webhook
Blast Radius
github.com/argoproj/argo-cd/v2🐹github.com/argoproj/argo-cd/v3🐹github.com/argoproj/argo-cd/v3🐹github.com/argoproj/argo-cd/v3Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
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 Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/argoproj/argo-cd/v2 | ≥ 2.9.0-rc1&&< 2.14.20 | 2.14.20 |
| 🐹Go | github.com/argoproj/argo-cd/v3 | ≥ 3.2.0-rc1&&< 3.2.0-rc2 | 3.2.0-rc2 |
| 🐹Go | github.com/argoproj/argo-cd/v3 | ≥ 3.1.0-rc1&&< 3.1.8 | 3.1.8 |
| 🐹Go | github.com/argoproj/argo-cd/v3 | ≥ 3.0.0-rc1&&< 3.0.19 | 3.0.19 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/argoproj/argo-cd/v2. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/argoproj/argo-cd/v2 to 2.14.20 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-59538 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2025-59538 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2025-59538. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2025-59538 in your dependencies?
O3 detects CVE-2025-59538 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.