Denial of Service Vulnerability in Mesop by Mesop Developers
CVE-2026-77357

8.7HIGH

Key Information:

Vendor

Mesop-dev

Status
Mesop
Vendor
CVE Published:
25 August 2026

What is CVE-2026-77357?

Mesop, a Python-based UI framework for web applications, has a vulnerability that allows unauthenticated attackers to exploit a GET /hot-reload endpoint in applications running in debug mode. This flaw leads to the exhaustion of server worker threads due to an unbounded loop that relies on a user-supplied counter parameter. An attacker can send requests that consume worker resources, causing the server to become unresponsive and requiring manual intervention to restart. The issue is effectively mitigated in version 1.3.3.

Affected Version(s)

mesop < 1.3.3

References

https://github.com/mesop-dev/mesop/security/advisories/GH...
x_refsource_CONFIRM
https://github.com/mesop-dev/mesop/commit/2b8e7f2c349c9e2...
x_refsource_MISC
https://github.com/mesop-dev/mesop/releases/tag/v1.3.3
x_refsource_MISC

CVSS V4

Score:
8.7
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.