CVE-2025-30358: high-severity vulnerability in mesop-dev mesop
Mesop Class Pollution vulnerability leads to DoS and Jailbreak attacks
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.1epss 0.7%
Mesop is a Python-based UI framework that allows users to build web applications. A class pollution vulnerability in Mesop prior to version 0.14.1 allows attackers to overwrite global variables and class attributes in certain Mesop modules during runtime. This vulnerability could directly lead to a denial of service (DoS) attack against the server. Additionally, it could also result in other severe consequences given the application's implementation, such as identity confusion, where an attacker could impersonate an assistant or system role within conversations. This impersonation could potentially enable jailbreak attacks when interacting with large language models (LLMs). Just like the Javascript's prototype pollution, this vulnerability could leave a way for attackers to manipulate the intended data-flow or control-flow of the application at runtime and lead to severe consequences like remote code execution when gadgets are available. Users should upgrade to version 0.14.1 to obtain a fix for the issue.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
Affected products
mesop-dev · mesopRelated CVEs — mesop-dev mesop
In the same product, most dangerous first.
CVE-2026-33057CRITICALMesop Affected by Unauthenticated Remote Code Execution via Test Suite Route /exec-pyEPSS 5.4%CVE-2026-34824HIGHMesop: Unbounded Thread Creation in WebSocket Handler Leads to Denial of ServiceEPSS 0.8%CVE-2026-33054CRITICALMesop: Path Traversal utilizing `FileStateSessionBackend` leads to Application Denial of Service and File Write/DeletionEPSS 0.7%CVE-2026-77357HIGHMesop: DoS in /hot-reload endpoint allows unauthenticated attacker to exhaust worker threads and crash the serverEPSS 0.5%CVE-2026-93421MEDIUMMesop: Unauthenticated ANSI Escape Sequence Injection in CSP Reporting EndpointEPSS 0.5%