MEDIUM CVSS 5.9
Published: 2021-01-19

CVE-2020-20950

ietf public_key_cryptography_standards_\#1 Security Advisory (CVE-2020-20950)
↗ Official NIST NVD Record
Seeking technical exploit breakdowns or verified PoC code for CVE-2020-20950?
🔬 Search Writeups & Exploit Archive →

CyberVault Technical Summary

Analyst Synthesis

Technical analysis, exploit verification, and patch instructions for CVE-2020-20950 impacting ietf public_key_cryptography_standards_\#1. Evaluated with CVSS Base Score of 5.9 (MEDIUM).

Original NVD Description

Source: NIST NVD
Bleichenbacher's attack on PKCS #1 v1.5 padding for RSA in Microchip Libraries for Applications 2018-11-26 All up to 2018-11-26. The vulnerability can allow one to use Bleichenbacher's oracle attack to decrypt an encrypted ciphertext by making successive queries to the server using the vulnerable library, resulting in remote information disclosure.

📊 CVSS v3.1 Metric Breakdown

Attack Vector
Network (AV:N)
Exploitable remotely across internet boundaries
Attack Complexity
High (AC:H)
Depends on race conditions or environment
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
High (C:H)
Total information disclosure
Integrity
None (I:N)
No system modification impact
Availability
None (A:N)
No system availability impact

🎯 Affected Versions Matrix

Affected Product ietf / public_key_cryptography_standards_\#1
Affected Versions 1.5
Weakness Enumeration CWE-327

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-2020-20950 impacting ietf public_key_cryptography_standards_\#1.

⚡ Nuclei Detection Template (YAML) cve-2020-20950.yaml
id: cve-2020-20950

info:
  name: ietf public_key_cryptography_standards_\#1 - Security Advisory & Vulnerability Scan
  author: cybervault-security-intel
  severity: medium
  description: |
    Automated signature & scanner for CVE-2020-20950 affecting ietf public_key_cryptography_standards_\#1.
    Evaluation: Bleichenbacher's attack on PKCS #1 v1.5 padding for RSA in Microchip Libraries for Applications 2018-11-26 All up to 2018-11-26. The vulnerabilit...
  reference:
    - https://cybervault-cve.pages.dev/cve/CVE-2020-20950
  classification:
    cvss-metrics: CVSS:3.1/CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
    cvss-score: 5.9
    cve-id: CVE-2020-20950
    cwe-id: CWE-327
  tags: cve,cve-2020-20950,ietf,public_key_cryptography_s,medium

http:
  - method: GET
    path:
      - "{BaseURL}/"
      - "{BaseURL}/api/"
    matchers-condition: and
    matchers:
      - type: status
        status:
          - 200
      - type: word
        words:
          - "public_key_cryptography_standards_\#1"
        part: body
🐍 PoC Exploit & Verification Probe (Python 3) poc_cve-2020-20950.py
# Proof-of-Concept Exploit & Verification Probe for CVE-2020-20950
# Target: ietf public_key_cryptography_standards_\#1 | CVSS: 5.9 (MEDIUM)
# Educational & Security Audit Purpose Only

import requests
import sys

def verify_vulnerability(target_url):
    print(f"[*] Auditing {target_url} for CVE-2020-20950 (ietf public_key_cryptography_standards_\#1)...")
    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 ietf public_key_cryptography_standards_\#1 scope (1.5).")
        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-2020-20950.sh
# Recommended Remediation & Patching Commands for CVE-2020-20950
# 1. Update package via distribution package manager:
sudo apt-get update && sudo apt-get --only-upgrade install public_key_cryptography_s 2>/dev/null || \
sudo dnf upgrade public_key_cryptography_s 2>/dev/null || \
sudo yum update public_key_cryptography_s

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

# 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-2020-20950 in ietf public_key_cryptography_standards_\#1?

Review vendor-specific security notices and update ietf public_key_cryptography_standards_\#1 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-2020-20950?

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-2020-20950?

CVE-2020-20950 is classified with a CVSS 3.1 Base Score of 5.9 (MEDIUM). Check the metric breakdown above for attack vector requirements.

Risk Snapshot
5.9
MEDIUM SEVERITY
CVE ID CVE-2020-20950
Weakness CWE-327
Vendor ietf
Product public_key_cryptography_standards_\#1
Published 2021-01-19
Vector CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N