Skip to content

CVE-2020-17496 — vBulletin 5.5.4 through 5.6.2 allows remote command execution via crafted subWidgets data…

Key facts

CVE-2020-17496 is a Critical (9.8) vulnerability: vBulletin 5.5.4 through 5.6.2 allows remote command execution via crafted subWidgets data…. This entry ships a detection-only PoC and a Docker test lab. It is on the CISA Known Exploited Vulnerabilities (KEV) catalog (added 2021-11-03), confirming active exploitation in the wild.

Actively exploited — on the CISA KEV catalog

CVE-2020-17496 is listed on the CISA Known Exploited Vulnerabilities (KEV) catalog (added 2021-11-03), confirming exploitation in the wild. Federal remediation deadline: 2022-05-03. Prioritise patching and deploy the detection and prevention rules below.
CVE CVE-2020-17496
Severity Critical (9.8)
CISA KEV Actively exploited (added 2021-11-03)
Detection / prevention —
PoC poc.py
Source 2020/CVE-2020-17496/

Details

English | 한국어

Description

vBulletin 5.5.4 through 5.6.2 allows remote command execution via crafted subWidgets data in an ajax/render/widget_tabbedcontainer_tab_panel request. NOTE: this issue exists because of an incomplete fix for CVE-2019-16759.

Vulnerability Details

Property Value
CVE ID CVE-2020-17496
CVSS Score 9.8

Proof of Concept

Download

# Download PoC script
curl -O https://raw.githubusercontent.com/fankh/vulnerability-poc/main/2020/CVE-2020-17496/poc.py

Usage

# Run PoC against target
python3 poc.py --target <TARGET_URL>

# With authentication
python3 poc.py --target <TARGET_URL> --username <USER> --password <PASS>

⚠️ Warning: This PoC is for authorized security testing only. It uses detection-only techniques and does not exploit or damage target systems.

Test Lab

This repository includes a Docker-based test environment with both vulnerable and patched applications.

Quick Start

# Clone and navigate to CVE directory
cd CVE-2020-17496

# Start both applications
docker-compose up -d

# Run tests
./run-tests.sh    # Linux/Mac
./run-tests.ps1   # Windows PowerShell

Application Endpoints

Application URL Status
Vulnerable App http://localhost:8080 Shows vulnerability
Patched App http://localhost:8081 Demonstrates fix

Directory Structure

├── README.md           # English documentation
├── README_KO.md        # Korean documentation
├── poc.py              # PoC detection script
├── docker-compose.yml  # Container orchestration
├── run-tests.sh        # Linux/Mac test runner
├── run-tests.ps1       # Windows test runner
├── vulnerable-app/     # Vulnerable version
│   ├── app.py
│   ├── Dockerfile
│   └── requirements.txt
└── patched-app/        # Fixed version
    ├── app.py
    ├── Dockerfile
    └── requirements.txt

References

  • https://blog.exploitee.rs/2020/exploiting-vbulletin-a-tale-of-patch-fail/
  • https://cwe.mitre.org/data/definitions/78.html
  • https://forum.vbulletin.com/forum/vbulletin-announcements/vbulletin-announcements_aa/4445227-vbulletin-5-6-0-5-6-1-5-6-2-security-patch
  • https://seclists.org/fulldisclosure/2020/Aug/5
  • https://blog.exploitee.rs/2020/exploiting-vbulletin-a-tale-of-patch-fail/
  • https://cwe.mitre.org/data/definitions/78.html
  • https://forum.vbulletin.com/forum/vbulletin-announcements/vbulletin-announcements_aa/4445227-vbulletin-5-6-0-5-6-1-5-6-2-security-patch
  • https://seclists.org/fulldisclosure/2020/Aug/5
  • https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-17496

Generated by PoC Generator on 2026-07-01T10:54:28.23661382

Frequently asked questions

What is CVE-2020-17496?

CVE-2020-17496 is a Critical (9.8) vulnerability: vBulletin 5.5.4 through 5.6.2 allows remote command execution via crafted subWidgets data…. This entry ships a detection-only PoC and a Docker test lab. It is on the CISA Known Exploited Vulnerabilities (KEV) catalog (added 2021-11-03), confirming active exploitation in the wild.

How do I detect CVE-2020-17496?

Run the detection-only PoC included with this entry against your Docker test lab to confirm whether a target is affected; pair it with your own IDS logging.

How do I block or mitigate CVE-2020-17496?

Upgrade to a fixed version per the vendor advisory; the NVD record lists the affected versions. Use the included PoC to verify your remediation.

Is CVE-2020-17496 actively exploited?

Yes. CVE-2020-17496 is on the CISA Known Exploited Vulnerabilities (KEV) catalog, added 2021-11-03, which means it has been exploited in the wild. CISA set a federal remediation deadline of 2022-05-03. Prioritise patching and deploy the detection and prevention rules above.

For authorized security testing and research only. See the full source and NVD record.