CVE-2026-33057

Mesop Affected by Unauthenticated Remote Code Execution via Test Suite Route /exec-py

Published Mar 20, 2026 CVSS 3.1 · 9.8 Critical EPSS 7.1% KEV · Not listed

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.

Analysis

Technical impact

The vulnerability allows an attacker to execute arbitrary Python code on the host. An insecure /exec‑py route in Mesop’s ai testing module accepts base64‑encoded Python code and executes it without authentication or validation, leading to uncontrolled code execution on the server and representing a classic code injection flaw identified as CWE‑94.

Affected Systems

The affected product is Mesop from mesop‑dev. Versions 1.2.2 and earlier are impacted; the issue was fixed in 1.2.3.

Risk and Exploitability

With a CVSS score of 9.8 the risk is extremely high. The EPSS score is 7%, indicating a lower public exploitation probability, but the vulnerability can be triggered by any unauthenticated HTTP request to the /exec‑py endpoint, which can be accessed by anyone able to route traffic to the Mesop application. The non‑authenticatable route allows immediate host‑level command execution and is not listed in the CISA KEV catalog.

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

mesop-dev

mesop

affected

Version	Status	Constraints
`< 1.2.3`	affected	—

Configuration 1 [-]

cpe:2.3:a:mesop-dev:mesop:*:*:*:*:*:*:*:*

No data.

Vendor Product Versions

Mesop-dev

Mesop

Version	Status	Scheme	Platform
`[0,1.2.3)`	affected	semver	—

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

Upgrade Mesop to version 1.2.3 or later.
If upgrading is not possible immediately, disable or remove the /exec‑py route (or the ai/sandbox/wsgi_app debugging server).
Restrict network exposure of the Mesop application, ensuring only trusted hosts can reach the /exec‑py endpoint.

Generated by OpenCVE AI on November 8, 2026 at 14:50 UTC.

Tracking

Advisories

Source	ID	Title
Github GHSA	GHSA-gjgx-rvqr-6w6v	Mesop Affected by Unauthenticated Remote Code Execution via Test Suite Route /exec-py

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploit prediction score: 7.1% (7.072% probability within 30 days)

Exploitation poc

Automatable yes

Technical Impact total

References

Link	Providers
https://github.com/mesop-dev/mesop/commit/825f55970c20686de3f28e2c66df4d74e9d4db47
https://github.com/mesop-dev/mesop/security/advisories/GHSA-gjgx-rvqr-6w6v

History

Mar 25, 2026 2:15 PM Scoring metrics updated View changes

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}`

Mar 24, 2026 4:15 PM Affected versions updated View changes

Type	Values Removed	Values Added
CPEs		cpe:2.3:a:mesop-dev:mesop::::::::

Mar 20, 2026 9:00 AM First appearance in the feed. Affected vendors updated View changes

Type	Values Removed	Values Added
First Time appeared		Mesop-dev Mesop-dev mesop
Vendors & Products		Mesop-dev Mesop-dev mesop

Mar 20, 2026 7:45 AM Description updated. Title updated. Weaknesses updated. Added references. Scoring metrics updated View changes

Type	Values Removed	Values Added
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.
Title		Mesop Affected by Unauthenticated Remote Code Execution via Test Suite Route /exec-py
Weaknesses		CWE-94
References		https://github.com/mesop-dev/mesop/commit/825f55970c20686de3f28e2c66df4d74e9d4db47 https://github.com/mesop-dev/mesop/security/advisories/GHSA-gjgx-rvqr-6w6v
Metrics		cvssV3_1 `{'score': 9.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}`