Regular Expression Vulnerability in Checkmate by Bluewave Labs
CVE-2026-70656

4.9MEDIUM

Key Information:

Vendor

Bluewave-labs

Status
Checkmate
Vendor
CVE Published:
21 August 2026

What is CVE-2026-70656?

An authentication issue in Checkmate allows an admin or superadmin to insert a malicious regular expression in the expectedValue field for HTTP monitor matching. This vulnerability arises due to the synchronous evaluation of the regex against untrusted HTTP response bodies, leading to a potential Denial of Service (DoS) by freezing API endpoints and disrupting WebSocket connections. Users are strongly advised to upgrade to version 3.9.2, which resolves this critical issue.

Affected Version(s)

Checkmate >= 3.5.1, < 3.9.2

References

https://github.com/bluewave-labs/Checkmate/security/advis...
x_refsource_CONFIRM
https://github.com/bluewave-labs/Checkmate/commit/0df71d6...
x_refsource_MISC
https://github.com/bluewave-labs/Checkmate/commit/adba252...
x_refsource_MISC

CVSS V3.1

Score:
4.9
Severity:
MEDIUM
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
High
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.