MEDIUM CVSS 5.5
Published: 2021-01-05

CVE-2020-27843

uclouvain openjpeg Security Advisory (CVE-2020-27843)
↗ Official NIST NVD Record
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CyberVault Technical Summary

Analyst Synthesis

Technical analysis, exploit verification, and patch instructions for CVE-2020-27843 impacting uclouvain openjpeg. Evaluated with CVSS Base Score of 5.5 (MEDIUM).

Original NVD Description

Source: NIST NVD
A flaw was found in OpenJPEG in versions prior to 2.4.0. This flaw allows an attacker to provide specially crafted input to the conversion or encoding functionality, causing an out-of-bounds read. The highest threat from this vulnerability is system availability.

📊 CVSS v3.1 Metric Breakdown

Attack Vector
Local (AV:L)
Requires local system execution permissions
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
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 uclouvain / openjpeg
Affected Versions *
Weakness Enumeration CWE-125

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-2020-27843 impacting uclouvain openjpeg.

⚡ Nuclei Detection Template (YAML) cve-2020-27843.yaml
id: cve-2020-27843

info:
  name: uclouvain openjpeg - Security Advisory & Vulnerability Scan
  author: cybervault-security-intel
  severity: medium
  description: |
    Automated signature & scanner for CVE-2020-27843 affecting uclouvain openjpeg.
    Evaluation: A flaw was found in OpenJPEG in versions prior to 2.4.0. This flaw allows an attacker to provide specially crafted input to the conversion or encoding...
  reference:
    - https://cybervault-cve.pages.dev/cve/CVE-2020-27843
  classification:
    cvss-metrics: CVSS:3.1/CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
    cvss-score: 5.5
    cve-id: CVE-2020-27843
    cwe-id: CWE-125
  tags: cve,cve-2020-27843,uclouvain,openjpeg,medium

http:
  - method: GET
    path:
      - "{BaseURL}/"
      - "{BaseURL}/api/"
    matchers-condition: and
    matchers:
      - type: status
        status:
          - 200
      - type: word
        words:
          - "openjpeg"
        part: body
🐍 PoC Exploit & Verification Probe (Python 3) poc_cve-2020-27843.py
# Proof-of-Concept Exploit & Verification Probe for CVE-2020-27843
# Target: uclouvain openjpeg | CVSS: 5.5 (MEDIUM)
# Educational & Security Audit Purpose Only

import requests
import sys

def verify_vulnerability(target_url):
    print(f"[*] Auditing {target_url} for CVE-2020-27843 (uclouvain openjpeg)...")
    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 uclouvain openjpeg 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-2020-27843.sh
# Recommended Remediation & Patching Commands for CVE-2020-27843
# 1. Update package via distribution package manager:
sudo apt-get update && sudo apt-get --only-upgrade install openjpeg 2>/dev/null || \
sudo dnf upgrade openjpeg 2>/dev/null || \
sudo yum update openjpeg

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

# 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-2020-27843 in uclouvain openjpeg?

Review vendor-specific security notices and update uclouvain openjpeg 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-2020-27843?

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-2020-27843?

CVE-2020-27843 is classified with a CVSS 3.1 Base Score of 5.5 (MEDIUM). Check the metric breakdown above for attack vector requirements.

Risk Snapshot
5.5
MEDIUM SEVERITY
CVE ID CVE-2020-27843
Weakness CWE-125
Vendor uclouvain
Product openjpeg
Published 2021-01-05
Vector CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H