Vulnerability in Mesop-Dev Mesop

CVE-2025-30358

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.

Vulnerability class: Mass Assignment

EPSS: 0.006 (46.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-30358?
CVE-2025-30358 is a high-severity vulnerability in Mesop-Dev Mesop, classified under Improperly Controlled Modification of Dynamically-Determined Object Attributes. CVSS score: 8.1/10. Published 2025-03-27.
How severe is CVE-2025-30358?
High severity. CVSS v3 base score is 8.1 out of 10.