Description

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.

Classification

CVE ID: CVE-2025-30358

CVSS Base Severity: HIGH

CVSS Base Score: 8.1

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H

Affected Products

Vendor: mesop-dev

Product: mesop

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.32% (probability of being exploited)

EPSS Percentile: 54.27% (scored less or equal to compared to others)

EPSS Date: 2025-04-25 (when was this score calculated)

References

https://nvd.nist.gov/vuln/detail/CVE-2025-30358
https://github.com/mesop-dev/mesop/security/advisories/GHSA-f3mf-hm6v-jfhh
https://github.com/mesop-dev/mesop/commit/748e20d4a363d89b841d62213f5b0c6b4bed788f

Timeline