{"cve":"CVE-2026-70656","nvd":{"published":"2026-08-21T18:16:50.277","modified":"2026-10-14T19:10:00.297","status":"Deferred","description":"Checkmate is an open-source, self-hosted tool designed to track and monitor server hardware, uptime, response times, and incidents in real-time with beautiful visualizations. From 3.5.1 until 3.9.2, an authenticated admin or superadmin can set matchMethod to regex and place a malicious expression in the expectedValue field for advanced HTTP monitor matching. server/src/api/validation/monitorValidation.ts accepts the expression, and server/src/service/network/AdvancedMatcher.ts synchronously evaluates it against an attacker-controlled HTTP response body on the Node.js main event loop without a timeout or worker isolation, allowing catastrophic backtracking to freeze API endpoints, monitor checks, and WebSocket connections for all users. This issue is fixed in version 3.9.2.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H","score":4.9},"cwes":["CWE-1333"],"references":["https://github.com/bluewave-labs/Checkmate/commit/0df71d6356c87c747e0b796b0c34e33f2a5203fa","https://github.com/bluewave-labs/Checkmate/commit/adba25269c455878bf8065bc28cfe5d74e58692f","https://github.com/bluewave-labs/Checkmate/commit/d5ec2936ad77ab773529057b442a6eb55dd578eb","https://github.com/bluewave-labs/Checkmate/releases/tag/v3.9.2","https://github.com/bluewave-labs/Checkmate/security/advisories/GHSA-4c6j-p2cv-wf56"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:49:38.260478770+00:00"},"epss":{"cve":"CVE-2026-70656","score":0.00587,"percentile":0.47801,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}