MEDIUM CVSS 6.1
Published: 2017-05-22

CVE-2017-2171

bestwebsoft captcha Security Advisory (CVE-2017-2171)
↗ Official NIST NVD Record
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CyberVault Technical Summary

Analyst Synthesis

Technical analysis, exploit verification, and patch instructions for CVE-2017-2171 impacting bestwebsoft captcha. Evaluated with CVSS Base Score of 6.1 (MEDIUM).

Original NVD Description

Source: NIST NVD
Cross-site scripting vulnerability in Captcha prior to version 4.3.0, Car Rental prior to version 1.0.5, Contact Form Multi prior to version 1.2.1, Contact Form prior to version 4.0.6, Contact Form to DB prior to version 1.5.7, Custom Admin Page prior to version 0.1.2, Custom Fields Search prior to version 1.3.2, Custom Search prior to version 1.36, Donate prior to version 2.1.1, Email Queue prior to version 1.1.2, Error Log Viewer prior to version 1.0.6, Facebook Button prior to version 2.54, Featured Posts prior to version 1.0.1, Gallery Categories prior to version 1.0.9, Gallery prior to version 4.5.0, Google +1 prior to version 1.3.4, Google AdSense prior to version 1.44, Google Analytics prior to version 1.7.1, Google Captcha (reCAPTCHA) prior to version 1.28, Google Maps prior to version 1.3.6, Google Shortlink prior to version 1.5.3, Google Sitemap prior to version 3.0.8, Htaccess prior to version 1.7.6, Job Board prior to version 1.1.3, Latest Posts prior to version 0.3, Limit Attempts prior to version 1.1.8, LinkedIn prior to version 1.0.5, Multilanguage prior to version 1.2.2, PDF & Print prior to version 1.9.4, Pagination prior to version 1.0.7, Pinterest prior to version 1.0.5, Popular Posts prior to version 1.0.5, Portfolio prior to version 2.4, Post to CSV prior to version 1.3.1, Profile Extra prior to version 1.0.7. PromoBar prior to version 1.1.1, Quotes and Tips prior to version 1.32, Re-attacher prior to version 1.0.9, Realty prior to version 1.1.0, Relevant - Related Posts prior to version 1.2.0, Sender prior to version 1.2.1, SMTP prior to version 1.1.0, Social Buttons Pack prior to version 1.1.1, Subscriber prior to version 1.3.5, Testimonials prior to version 0.1.9, Timesheet prior to version 0.1.5, Twitter Button prior to version 2.55, User Role prior to version 1.5.6, Updater prior to version 1.35, Visitors Online prior to version 1.0.0, and Zendesk Help Center prior to version 1.0.5 allows remote attackers to inject arbitrary web script or HTML via the function to display the BestWebSoft menu.

📊 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
Changed (S:C)
Impacts components beyond caller authority
Confidentiality
Low (C:L)
Partial information leakage
Integrity
Low (I:L)
Partial data modification possible
Availability
None (A:N)
No system availability impact

🎯 Affected Versions Matrix

Affected Product bestwebsoft / captcha
Affected Versions *
Weakness Enumeration CWE-79

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-2017-2171 impacting bestwebsoft captcha.

⚡ Nuclei Detection Template (YAML) cve-2017-2171.yaml
id: cve-2017-2171

info:
  name: bestwebsoft captcha - Security Advisory & Vulnerability Scan
  author: cybervault-security-intel
  severity: medium
  description: |
    Automated signature & scanner for CVE-2017-2171 affecting bestwebsoft captcha.
    Evaluation: Cross-site scripting vulnerability in Captcha prior to version 4.3.0, Car Rental prior to version 1.0.5, Contact Form Multi prior to version 1.2.1, Co...
  reference:
    - https://cybervault-cve.pages.dev/cve/CVE-2017-2171
  classification:
    cvss-metrics: CVSS:3.1/CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
    cvss-score: 6.1
    cve-id: CVE-2017-2171
    cwe-id: CWE-79
  tags: cve,cve-2017-2171,bestwebsoft,captcha,medium

http:
  - method: GET
    path:
      - "{BaseURL}/"
      - "{BaseURL}/api/"
    matchers-condition: and
    matchers:
      - type: status
        status:
          - 200
      - type: word
        words:
          - "captcha"
        part: body
🐍 PoC Exploit & Verification Probe (Python 3) poc_cve-2017-2171.py
# Proof-of-Concept Exploit & Verification Probe for CVE-2017-2171
# Target: bestwebsoft captcha | CVSS: 6.1 (MEDIUM)
# Educational & Security Audit Purpose Only

import requests
import sys

def verify_vulnerability(target_url):
    print(f"[*] Auditing {target_url} for CVE-2017-2171 (bestwebsoft captcha)...")
    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 bestwebsoft captcha 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-2017-2171.sh
# Recommended Remediation & Patching Commands for CVE-2017-2171
# 1. Update package via distribution package manager:
sudo apt-get update && sudo apt-get --only-upgrade install captcha 2>/dev/null || \
sudo dnf upgrade captcha 2>/dev/null || \
sudo yum update captcha

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

# 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.

🔗 Verified Technical References

❓ Frequently Asked Questions (FAQ) & Remediation Guide

How do I fix CVE-2017-2171 in bestwebsoft captcha?

Review vendor-specific security notices and update bestwebsoft captcha 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-2017-2171?

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-2017-2171?

CVE-2017-2171 is classified with a CVSS 3.1 Base Score of 6.1 (MEDIUM). Check the metric breakdown above for attack vector requirements.

Risk Snapshot
6.1
MEDIUM SEVERITY
CVE ID CVE-2017-2171
Weakness CWE-79
Vendor bestwebsoft
Product captcha
Published 2017-05-22
Vector CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N