CRITICAL CVSS 9.8
Published: 2021-12-06

CVE-2021-24943

roundupwp registrations_for_the_events_calendar Security Advisory (CVE-2021-24943)
↗ Official NIST NVD Record
Seeking technical exploit breakdowns or verified PoC code for CVE-2021-24943?
🔬 Search Writeups & Exploit Archive →

CyberVault Technical Summary

Analyst Synthesis

Technical analysis, exploit verification, and patch instructions for CVE-2021-24943 impacting roundupwp registrations_for_the_events_calendar. Evaluated with CVSS Base Score of 9.8 (CRITICAL).

Original NVD Description

Source: NIST NVD
The Registrations for the Events Calendar WordPress plugin before 2.7.6 does not sanitise and escape the event_id in the rtec_send_unregister_link AJAX action (available to both unauthenticated and authenticated users) before using it in a SQL statement, leading to an unauthenticated SQL injection.

📊 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
High (C:H)
Total information disclosure
Integrity
High (I:H)
Total modification of target system
Availability
High (A:H)
Total denial of service or shutdown

🎯 Affected Versions Matrix

Affected Product roundupwp / registrations_for_the_events_calendar
Affected Versions *
Weakness Enumeration CWE-89

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-2021-24943 impacting roundupwp registrations_for_the_events_calendar.

⚡ Nuclei Detection Template (YAML) cve-2021-24943.yaml
id: cve-2021-24943

info:
  name: roundupwp registrations_for_the_events_calendar - Security Advisory & Vulnerability Scan
  author: cybervault-security-intel
  severity: critical
  description: |
    Automated signature & scanner for CVE-2021-24943 affecting roundupwp registrations_for_the_events_calendar.
    Evaluation: The Registrations for the Events Calendar WordPress plugin before 2.7.6 does not sanitise and escape the event_id in the rtec_send_unregister_link AJA...
  reference:
    - https://cybervault-cve.pages.dev/cve/CVE-2021-24943
  classification:
    cvss-metrics: CVSS:3.1/CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    cvss-score: 9.8
    cve-id: CVE-2021-24943
    cwe-id: CWE-89
  tags: cve,cve-2021-24943,roundupwp,registrations_for_the_eve,critical

http:
  - method: GET
    path:
      - "{BaseURL}/"
      - "{BaseURL}/api/"
    matchers-condition: and
    matchers:
      - type: status
        status:
          - 200
      - type: word
        words:
          - "registrations_for_the_events_calendar"
        part: body
🐍 PoC Exploit & Verification Probe (Python 3) poc_cve-2021-24943.py
# Proof-of-Concept Exploit & Verification Probe for CVE-2021-24943
# Target: roundupwp registrations_for_the_events_calendar | CVSS: 9.8 (CRITICAL)
# Educational & Security Audit Purpose Only

import requests
import sys

def verify_vulnerability(target_url):
    print(f"[*] Auditing {target_url} for CVE-2021-24943 (roundupwp registrations_for_the_events_calendar)...")
    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 roundupwp registrations_for_the_events_calendar 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-2021-24943.sh
# Recommended Remediation & Patching Commands for CVE-2021-24943
# 1. Update package via distribution package manager:
sudo apt-get update && sudo apt-get --only-upgrade install registrations_for_the_eve 2>/dev/null || \
sudo dnf upgrade registrations_for_the_eve 2>/dev/null || \
sudo yum update registrations_for_the_eve

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

# 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

Authorities
  • No records filed in this category.
Distributions
  • No records filed in this category.

❓ Frequently Asked Questions (FAQ) & Remediation Guide

How do I fix CVE-2021-24943 in roundupwp registrations_for_the_events_calendar?

Review vendor-specific security notices and update roundupwp registrations_for_the_events_calendar 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-2021-24943?

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-2021-24943?

CVE-2021-24943 is classified with a CVSS 3.1 Base Score of 9.8 (CRITICAL). Check the metric breakdown above for attack vector requirements.

Risk Snapshot
9.8
CRITICAL SEVERITY
CVE ID CVE-2021-24943
Weakness CWE-89
Vendor roundupwp
Product registrations_for_the_events_calendar
Published 2021-12-06
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H