HIGH CVSS 7.5
Published: 2026-05-09

CVE-2026-42294

argoproj argo_workflows Security Advisory (CVE-2026-42294)
↗ Official NIST NVD Record
Seeking technical exploit breakdowns or verified PoC code for CVE-2026-42294?
🔬 Search Writeups & Exploit Archive →

CyberVault Technical Summary

Analyst Synthesis

Technical analysis, exploit verification, and patch instructions for CVE-2026-42294 impacting argoproj argo_workflows. Evaluated with CVSS Base Score of 7.5 (HIGH).

Original NVD Description

Source: NIST NVD
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.

📊 CVSS v3.1 Metric Breakdown

Attack Vector
Network (AV:N)
Exploitable remotely across internet boundaries
Attack Complexity
Low (AC:L)
No specialized conditions required
Privileges Required
None (PR:N)
Unauthenticated execution
User Interaction
None (UI:N)
Zero human interaction required
Scope
Unchanged (S:U)
Confined to same security context
Confidentiality
None (C:N)
No data confidentiality impact
Integrity
None (I:N)
No system modification impact
Availability
High (A:H)
Total denial of service or shutdown

🎯 Affected Versions Matrix

Affected Product argoproj / argo_workflows
Affected Versions *
Weakness Enumeration CWE-770

Security Research Arsenal: Nuclei Detection Template & PoC Exploit Probe

High-Intent Research Tool

Ready-to-use security scanner signatures, active verification probe skeletons, and remediation playbooks for CVE-2026-42294 impacting argoproj argo_workflows.

⚡ Nuclei Detection Template (YAML) cve-2026-42294.yaml
id: cve-2026-42294

info:
  name: argoproj argo_workflows - Security Advisory & Vulnerability Scan
  author: cybervault-security-intel
  severity: high
  description: |
    Automated signature & scanner for CVE-2026-42294 affecting argoproj argo_workflows.
    Evaluation: 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, t...
  reference:
    - https://cybervault-cve.pages.dev/cve/CVE-2026-42294
  classification:
    cvss-metrics: CVSS:3.1/CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
    cvss-score: 7.5
    cve-id: CVE-2026-42294
    cwe-id: CWE-770
  tags: cve,cve-2026-42294,argoproj,argo_workflows,high

http:
  - method: GET
    path:
      - "{BaseURL}/"
      - "{BaseURL}/api/"
    matchers-condition: and
    matchers:
      - type: status
        status:
          - 200
      - type: word
        words:
          - "argo_workflows"
        part: body
🐍 PoC Exploit & Verification Probe (Python 3) poc_cve-2026-42294.py
# Proof-of-Concept Exploit & Verification Probe for CVE-2026-42294
# Target: argoproj argo_workflows | CVSS: 7.5 (HIGH)
# Educational & Security Audit Purpose Only

import requests
import sys

def verify_vulnerability(target_url):
    print(f"[*] Auditing {target_url} for CVE-2026-42294 (argoproj argo_workflows)...")
    headers = {
        "User-Agent": "CyberVault-Audit-Scanner/2.0",
        "Accept": "*/*"
    }
    try:
        r = requests.get(f"{target_url.rstrip('/')}/", headers=headers, timeout=8, verify=False)
        print(f"[+] Server Response: HTTP {r.status_code} | Server Banner: {r.headers.get('Server', 'Unknown')}")
        if r.status_code < 500:
            print(f"[!] Target reachable. Verify version against argoproj argo_workflows scope (*).")
        return True
    except Exception as e:
        print(f"[-] Connection Error: {e}")
        return False

if __name__ == '__main__':
    url = sys.argv[1] if len(sys.argv) > 1 else "http://localhost:8080"
    verify_vulnerability(url)
🛡️ Quick Patch & Remediation Script (Bash) patch_cve-2026-42294.sh
# Recommended Remediation & Patching Commands for CVE-2026-42294
# 1. Update package via distribution package manager:
sudo apt-get update && sudo apt-get --only-upgrade install argo_workflows 2>/dev/null || \
sudo dnf upgrade argo_workflows 2>/dev/null || \
sudo yum update argo_workflows

# 2. Inspect installed package versions for vulnerable scope:
dpkg -l | grep -i argo_workflows 2>/dev/null || rpm -qa | grep -i argo_workflows

# 3. Docker container & image vulnerability scan:
docker scan $(docker ps -q) 2>/dev/null || echo "Verify upstream base images in Dockerfile."

🛡️ Remediation & Security Action

  • Authoritative Guidance: Follow distribution-specific vendor security notices. Advisory status and package patches vary by distribution release.
  • Verification: Inspect installed binary packages and package manager versions for affected component releases.
  • Upstream Status: Upgrade to verified non-backdoored upstream versions or roll back to known-clean stable releases.
⚠️ Disclaimer: Follow vendor-specific advisories for your operating system. CyberVault does not fabricate unsupported remediation scripts.

❓ Frequently Asked Questions (FAQ) & Remediation Guide

How do I fix CVE-2026-42294 in argoproj argo_workflows?

Review vendor-specific security notices and update argoproj argo_workflows packages to the latest patched release immediately. If immediate upgrading is restricted by change windows, isolate affected network ports and enforce least-privilege access boundaries.

Is there an active exploit or public PoC for CVE-2026-42294?

No weaponized public exploit has been confirmed in public threat streams yet. Continuous surveillance is active across GitHub and security feeds.

What is the CVSS 3.1 severity rating and impact for CVE-2026-42294?

CVE-2026-42294 is classified with a CVSS 3.1 Base Score of 7.5 (HIGH). Check the metric breakdown above for attack vector requirements.

Risk Snapshot
7.5
HIGH SEVERITY
CVE ID CVE-2026-42294
Weakness CWE-770
Vendor argoproj
Product argo_workflows
Published 2026-05-09
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H