Skip to content

CVE-2026-52843 — Lightpanda is a headless browser designed for AI and automation.

Key facts

CVE-2026-52843 is a Critical (9.3) vulnerability: Lightpanda is a headless browser designed for AI and automation.. This entry ships a detection-only PoC and a Docker test lab.

CVE CVE-2026-52843
Severity Critical (9.3)
Detection / prevention —
PoC poc.py
Source 2026/CVE-2026-52843/

Details

English | 한국어

Description

Lightpanda is a headless browser designed for AI and automation. Prior to 0.2.9, Lightpanda fetch() and XMLHttpRequest unconditionally attached session cookies to every HTTP request, ignoring credentials: omit, credentials: same-origin, credentials: include, and XMLHttpRequest.withCredentials, allowing an attacker-controlled origin in a Lightpanda session to issue authenticated cross-origin requests against a victim origin. This issue is fixed in version 0.2.9.

Vulnerability Details

Property Value
CVE ID CVE-2026-52843
CVSS Score 9.3

Proof of Concept

Download

# Download PoC script
curl -O https://raw.githubusercontent.com/fankh/vulnerability-poc/main/2026/CVE-2026-52843/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-2026-52843

# 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://github.com/lightpanda-io/browser/commit/2cdaac780bed65db98bbb6ed2ad5bc6011863c76
  • https://github.com/lightpanda-io/browser/pull/2155
  • https://github.com/lightpanda-io/browser/releases/tag/0.2.9
  • https://github.com/lightpanda-io/browser/security/advisories/GHSA-36mm-v3c2-24cc

Generated by PoC Generator on 2026-07-16T02:33:02.955751504

Frequently asked questions

What is CVE-2026-52843?

CVE-2026-52843 is a Critical (9.3) vulnerability: Lightpanda is a headless browser designed for AI and automation.. This entry ships a detection-only PoC and a Docker test lab.

How do I detect CVE-2026-52843?

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-2026-52843?

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


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