What’s Vulnerable › Vulnerabilities

CVE-2026-42294: Argo Workflows: Unauthenticated Memory Exhaustion (DoS) in Webhook Interceptor

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.6% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-05-09 · updated 2026-07-24
• Weakness: CWE-770

Description

Argo Workflows is an open source container-native workflow engine for orchestrating parallel jobs on Kubernetes. Prior to versions 3.7.14 and 4.0.5, the Webhook Interceptor loads the entire request body into memory before authenticating the request or verifying its signature. This occurs on the /api/v1/events/ endpoint, which is publicly accessible (albeit intended for webhooks). An attacker can send a request with an extremely large body (e.g., multiple gigabytes), causing the Argo Server to allocate excessive memory, potentially leading to an Out-Of-Memory (OOM) crash and denial of service. This issue has been patched in versions 3.7.14 and 4.0.5.

Affected products

• argoproj argo-workflows: before 3.7.14; from 4.0.0 before 4.0.5 — fixed in 3.7.14, 4.0.5

How to fix

Upgrade to a fixed version: argoproj argo-workflows 3.7.14, 4.0.5. Check the vendor advisory for mitigations.

References

• https://github.com/argoproj/argo-workflows/commit/7abb4de6c3599e2d5d960ba4d5de4cf1df109965
• https://github.com/argoproj/argo-workflows/releases/tag/v3.7.14
• https://github.com/argoproj/argo-workflows/releases/tag/v4.0.5
• https://github.com/argoproj/argo-workflows/security/advisories/GHSA-jcc8-g2q4-9fxq
• https://access.redhat.com/security/cve/CVE-2026-42294
• https://bugzilla.redhat.com/show_bug.cgi?id=2468443
• https://github.com/argoproj/argo-workflows/security/advisories/GHSA-jcc8-g2q4-9fxq
• https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42294.json

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