{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-70656",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-08-04T21:48:08.612Z",
        "datePublished": "2026-08-21T17:59:28.639Z",
        "dateUpdated": "2026-08-21T18:07:11.885Z"
    },
    "containers": {
        "cna": {
            "title": "Checkmate: Regular Expression Denial of Service (ReDoS) via User-Controlled Regex in Monitor Advanced Matching",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-1333",
                            "lang": "en",
                            "description": "CWE-1333: Inefficient Regular Expression Complexity",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "attackComplexity": "LOW",
                        "attackVector": "NETWORK",
                        "availabilityImpact": "HIGH",
                        "baseScore": 4.9,
                        "baseSeverity": "MEDIUM",
                        "confidentialityImpact": "NONE",
                        "integrityImpact": "NONE",
                        "privilegesRequired": "HIGH",
                        "scope": "UNCHANGED",
                        "userInteraction": "NONE",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H",
                        "version": "3.1"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/bluewave-labs/Checkmate/security/advisories/GHSA-4c6j-p2cv-wf56",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/bluewave-labs/Checkmate/security/advisories/GHSA-4c6j-p2cv-wf56"
                },
                {
                    "name": "https://github.com/bluewave-labs/Checkmate/commit/0df71d6356c87c747e0b796b0c34e33f2a5203fa",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/bluewave-labs/Checkmate/commit/0df71d6356c87c747e0b796b0c34e33f2a5203fa"
                },
                {
                    "name": "https://github.com/bluewave-labs/Checkmate/commit/adba25269c455878bf8065bc28cfe5d74e58692f",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/bluewave-labs/Checkmate/commit/adba25269c455878bf8065bc28cfe5d74e58692f"
                },
                {
                    "name": "https://github.com/bluewave-labs/Checkmate/commit/d5ec2936ad77ab773529057b442a6eb55dd578eb",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/bluewave-labs/Checkmate/commit/d5ec2936ad77ab773529057b442a6eb55dd578eb"
                },
                {
                    "name": "https://github.com/bluewave-labs/Checkmate/releases/tag/v3.9.2",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/bluewave-labs/Checkmate/releases/tag/v3.9.2"
                }
            ],
            "affected": [
                {
                    "vendor": "bluewave-labs",
                    "product": "Checkmate",
                    "versions": [
                        {
                            "version": ">= 3.5.1, < 3.9.2",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-08-21T17:59:28.639Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "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."
                }
            ],
            "source": {
                "advisory": "GHSA-4c6j-p2cv-wf56",
                "discovery": "UNKNOWN"
            }
        },
        "adp": [
            {
                "references": [
                    {
                        "url": "https://github.com/bluewave-labs/Checkmate/security/advisories/GHSA-4c6j-p2cv-wf56",
                        "tags": [
                            "exploit"
                        ]
                    }
                ],
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-08-21T18:06:46.856684Z",
                                "id": "CVE-2026-70656",
                                "options": [
                                    {
                                        "Exploitation": "poc"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "partial"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2026-08-21T18:07:11.885Z"
                }
            }
        ]
    }
}