CVE-2026-33057 PoC — Mesop Affected by Unauthenticated Remote Code Execution via Test Suite Route /exec-py

Source

https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2026/CVE-2026-33057.yaml

Associated Vulnerability

Title:Mesop Affected by Unauthenticated Remote Code Execution via Test Suite Route /exec-py (CVE-2026-33057)
Description:Mesop is a Python-based UI framework that allows users to build web applications. In versions 1.2.2 and below, an explicit web endpoint inside the ai/ testing module infrastructure directly ingests untrusted Python code strings unconditionally without authentication measures, yielding standard Unrestricted Remote Code Execution. Any individual capable of routing HTTP logic to this server block will gain explicit host-machine command rights. The AI codebase package includes a lightweight debugging Flask server inside ai/sandbox/wsgi_app.py. The /exec-py route accepts base_64 encoded raw string payloads inside the code parameter natively evaluated by a basic POST web request. It saves it rapidly to the operating system logic path and injects it recursively using execute_module(module_path...). This issue has been fixed in version 1.2.3.

Description

Mesop <= 1.2.2 contains an unrestricted remote code execution caused by unauthenticated ingestion and execution of base64-encoded Python code in the /exec-py endpoint of ai/testing module, letting attackers execute arbitrary commands on the host, exploit requires HTTP access to the server.

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