MEDIUM CVSS 4.3
Published: 2022-11-25

CVE-2022-39339

nextcloud openid_connect_user_backend Security Advisory (CVE-2022-39339)
↗ Official NIST NVD Record
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CyberVault Technical Summary

Analyst Synthesis

Technical analysis, exploit verification, and patch instructions for CVE-2022-39339 impacting nextcloud openid_connect_user_backend. Evaluated with CVSS Base Score of 4.3 (MEDIUM).

Original NVD Description

Source: NIST NVD
user_oidc is an OpenID Connect user backend for Nextcloud. In versions prior to 1.2.1 sensitive information such as the OIDC client credentials and tokens are sent in plain text of HTTP without TLS. Any malicious actor with access to monitor user traffic may have been able to compromise account security. This issue has been addressed in in user_oidc v1.2.1. Users are advised to upgrade. Users unable to upgrade may use https to access Nextcloud. Set an HTTPS discovery URL in the provider settings (in Nextcloud OIDC admin settings).

📊 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
Required (UI:R)
User must click or open resource
Scope
Unchanged (S:U)
Confined to same security context
Confidentiality
Low (C:L)
Partial information leakage
Integrity
None (I:N)
No system modification impact
Availability
None (A:N)
No system availability impact

🎯 Affected Versions Matrix

Affected Product nextcloud / openid_connect_user_backend
Affected Versions *
Weakness Enumeration CWE-319

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-2022-39339 impacting nextcloud openid_connect_user_backend.

⚡ Nuclei Detection Template (YAML) cve-2022-39339.yaml
id: cve-2022-39339

info:
  name: nextcloud openid_connect_user_backend - Security Advisory & Vulnerability Scan
  author: cybervault-security-intel
  severity: medium
  description: |
    Automated signature & scanner for CVE-2022-39339 affecting nextcloud openid_connect_user_backend.
    Evaluation: user_oidc is an OpenID Connect user backend for Nextcloud. In versions prior to 1.2.1 sensitive information such as the OIDC client credentials and to...
  reference:
    - https://cybervault-cve.pages.dev/cve/CVE-2022-39339
  classification:
    cvss-metrics: CVSS:3.1/CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
    cvss-score: 4.3
    cve-id: CVE-2022-39339
    cwe-id: CWE-319
  tags: cve,cve-2022-39339,nextcloud,openid_connect_user_backe,medium

http:
  - method: GET
    path:
      - "{BaseURL}/"
      - "{BaseURL}/api/"
    matchers-condition: and
    matchers:
      - type: status
        status:
          - 200
      - type: word
        words:
          - "openid_connect_user_backend"
        part: body
🐍 PoC Exploit & Verification Probe (Python 3) poc_cve-2022-39339.py
# Proof-of-Concept Exploit & Verification Probe for CVE-2022-39339
# Target: nextcloud openid_connect_user_backend | CVSS: 4.3 (MEDIUM)
# Educational & Security Audit Purpose Only

import requests
import sys

def verify_vulnerability(target_url):
    print(f"[*] Auditing {target_url} for CVE-2022-39339 (nextcloud openid_connect_user_backend)...")
    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 nextcloud openid_connect_user_backend 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-2022-39339.sh
# Recommended Remediation & Patching Commands for CVE-2022-39339
# 1. Update package via distribution package manager:
sudo apt-get update && sudo apt-get --only-upgrade install openid_connect_user_backe 2>/dev/null || \
sudo dnf upgrade openid_connect_user_backe 2>/dev/null || \
sudo yum update openid_connect_user_backe

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

# 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-2022-39339 in nextcloud openid_connect_user_backend?

Review vendor-specific security notices and update nextcloud openid_connect_user_backend 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-2022-39339?

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-2022-39339?

CVE-2022-39339 is classified with a CVSS 3.1 Base Score of 4.3 (MEDIUM). Check the metric breakdown above for attack vector requirements.

Risk Snapshot
4.3
MEDIUM SEVERITY
CVE ID CVE-2022-39339
Weakness CWE-319
Vendor nextcloud
Product openid_connect_user_backend
Published 2022-11-25
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N