CVE-2026-34824

Mesop: Unbounded Thread Creation in WebSocket Handler Leads to Denial of Service

HIGH
7.5
CVSS Score
Published: April 3, 2026 at 10:41 PM UTC
Updated: July 24, 2026 at 10:20 PM UTC
1 product affected across 1 vendorMesop

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Severity
HIGH7.5
Exploit prediction
EPSS 0.7%
SSVC
PoC

Description

Mesop is a Python-based UI framework that allows users to build web applications. From version 1.2.3 to before version 1.2.5, an uncontrolled resource consumption vulnerability exists in the WebSocket implementation of the Mesop framework. An unauthenticated attacker can send a rapid succession of WebSocket messages, forcing the server to spawn an unbounded number of operating system threads. This leads to thread exhaustion and Out of Memory (OOM) errors, causing a complete Denial of Service (DoS) for any application built on the framework. This issue has been patched in version 1.2.5.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 1.2.51.2.3 ≤ v < 1.2.5
Affected range stops below 1.2.5, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (3)

x_refsource_CONFIRMExploitMitigationVendor Advisory
Source: cverecord
https://github.com/mesop-dev/mesop/security/advisories/GHSA-3jr7-6hqp-x679
x_refsource_MISCProductRelease Notes
Source: cverecord
https://github.com/mesop-dev/mesop/releases/tag/v1.2.5

SSVC — Action Prioritization

SSVCPoCAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.5HIGHGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-125CWE-770

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