CVE-2026-35640

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-35640", "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "state": "PUBLISHED", "assignerShortName": "VulnCheck", "dateReserved": "2026-04-04T12:30:33.464Z", "datePublished": "2026-04-09T21:27:08.792Z", "dateUpdated": "2026-06-23T16:16:00.938Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "shortName": "VulnCheck", "dateUpdated": "2026-06-23T16:16:00.938Z"}, "title": "OpenClaw < 2026.3.25 - Denial of Service via Unauthenticated Webhook Request Parsing", "descriptions": [{"lang": "en", "value": "OpenClaw before 2026.3.25 parses JSON request bodies before validating webhook signatures, allowing unauthenticated attackers to force resource-intensive parsing operations. Remote attackers can send malicious webhook requests to trigger denial of service by exhausting server resources through forced JSON parsing before signature rejection."}], "tags": ["x_open-source"], "datePublic": "2026-03-26T00:00:00.000Z", "problemTypes": [{"descriptions": [{"lang": "en", "cweId": "CWE-696", "description": "CWE-696: Incorrect Behavior Order", "type": "CWE"}]}], "affected": [{"vendor": "OpenClaw", "product": "OpenClaw", "defaultStatus": "unaffected", "packageURL": "pkg:npm/openclaw", "versions": [{"version": "0", "status": "affected", "versionType": "semver", "lessThan": "2026.3.25"}, {"version": "2026.3.25", "status": "unaffected", "versionType": "semver"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:openclaw:openclaw:*:*:*:*:*:node.js:*:*", "versionEndExcluding": "2026.3.25"}]}]}], "metrics": [{"format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}], "cvssV4_0": {"attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "NONE", "subConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "subIntegrityImpact": "NONE", "vulnAvailabilityImpact": "LOW", "subAvailabilityImpact": "NONE", "exploitMaturity": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "version": "4.0", "baseSeverity": "MEDIUM", "baseScore": 6.9, "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N"}}, {"format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}], "cvssV3_1": {"attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "LOW", "version": "3.1", "baseSeverity": "MEDIUM", "baseScore": 5.3, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"}}], "references": [{"url": "https://github.com/openclaw/openclaw/security/advisories/GHSA-3h52-cx59-c456", "name": "GitHub Security Advisory (GHSA-3h52-cx59-c456)", "tags": ["vendor-advisory"]}, {"url": "https://github.com/openclaw/openclaw/commit/5e8cb22176e9235e224be0bc530699261eb60e53", "name": "Patch Commit", "tags": ["patch"]}, {"name": "VulnCheck Advisory: OpenClaw < 2026.3.25 - Denial of Service via Unauthenticated Webhook Request Parsing", "tags": ["third-party-advisory"], "url": "https://www.vulncheck.com/advisories/openclaw-denial-of-service-via-unauthenticated-webhook-request-parsing"}], "credits": [{"lang": "en", "value": "tdjackey", "type": "reporter"}], "x_generator": {"engine": "vulncheck"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-04-10T12:25:51.531666Z", "id": "CVE-2026-35640", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"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": "2026-04-10T12:29:52.811Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-35640", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-04-10T12:25:51.531666Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-04-10T12:29:48.309Z"}}], "cna": {"tags": ["x_open-source"], "title": "OpenClaw < 2026.3.25 - Denial of Service via Unauthenticated Webhook Request Parsing", "credits": [{"lang": "en", "type": "reporter", "value": "tdjackey"}], "metrics": [{"format": "CVSS", "cvssV4_0": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 6.9, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "NONE", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "LOW", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "NONE", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "scenarios": [{"lang": "en", "value": "GENERAL"}]}, {"format": "CVSS", "cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.3, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "LOW", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "affected": [{"vendor": "OpenClaw", "product": "OpenClaw", "versions": [{"status": "affected", "version": "0", "lessThan": "2026.3.25", "versionType": "semver"}, {"status": "unaffected", "version": "2026.3.25", "versionType": "semver"}], "packageURL": "pkg:npm/openclaw", "defaultStatus": "unaffected"}], "datePublic": "2026-03-26T00:00:00.000Z", "references": [{"url": "https://github.com/openclaw/openclaw/security/advisories/GHSA-3h52-cx59-c456", "name": "GitHub Security Advisory (GHSA-3h52-cx59-c456)", "tags": ["third-party-advisory"]}, {"url": "https://github.com/openclaw/openclaw/commit/5e8cb22176e9235e224be0bc530699261eb60e53", "name": "Patch Commit", "tags": ["patch"]}, {"url": "https://www.vulncheck.com/advisories/openclaw-denial-of-service-via-unauthenticated-webhook-request-parsing", "name": "VulnCheck Advisory: OpenClaw < 2026.3.25 - Denial of Service via Unauthenticated Webhook Request Parsing", "tags": ["third-party-advisory"]}], "x_generator": {"engine": "vulncheck"}, "descriptions": [{"lang": "en", "value": "OpenClaw before 2026.3.25 parses JSON request bodies before validating webhook signatures, allowing unauthenticated attackers to force resource-intensive parsing operations. Remote attackers can send malicious webhook requests to trigger denial of service by exhausting server resources through forced JSON parsing before signature rejection."}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-696", "description": "CWE-696: Incorrect Behavior Order"}]}], "cpeApplicability": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:openclaw:openclaw:*:*:*:*:*:node.js:*:*", "vulnerable": true, "versionEndExcluding": "2026.3.25"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "shortName": "VulnCheck", "dateUpdated": "2026-04-09T21:27:08.792Z"}}}, "cveMetadata": {"cveId": "CVE-2026-35640", "state": "PUBLISHED", "dateUpdated": "2026-04-10T12:29:52.811Z", "dateReserved": "2026-04-04T12:30:33.464Z", "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "datePublished": "2026-04-09T21:27:08.792Z", "assignerShortName": "VulnCheck"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "packageURL": "pkg:npm/openclaw", "product": "OpenClaw", "vendor": "OpenClaw", "versions": [{"lessThan": "2026.3.25", "status": "affected", "version": "0", "versionType": "semver"}, {"status": "unaffected", "version": "2026.3.25", "versionType": "semver"}]}], "source": "disclosure@vulncheck.com"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:openclaw:openclaw:*:*:*:*:*:node.js:*:*", "matchCriteriaId": "AC9C9003-CE72-4BFC-85B4-1E778E125CB1", "versionEndExcluding": "2026.3.25", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "OpenClaw before 2026.3.25 parses JSON request bodies before validating webhook signatures, allowing unauthenticated attackers to force resource-intensive parsing operations. Remote attackers can send malicious webhook requests to trigger denial of service by exhausting server resources through forced JSON parsing before signature rejection."}, {"lang": "es", "value": "OpenClaw anterior a 2026.3.25 analiza cuerpos de solicitud JSON antes de validar firmas de webhook, permitiendo a atacantes no autenticados forzar operaciones de an\u00e1lisis que consumen muchos recursos. Atacantes remotos pueden enviar solicitudes de webhook maliciosas para desencadenar una denegaci\u00f3n de servicio agotando los recursos del servidor mediante el an\u00e1lisis JSON forzado antes del rechazo de la firma."}], "id": "CVE-2026-35640", "lastModified": "2026-11-11T23:10:00.263", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 5.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 1.4, "source": "disclosure@vulncheck.com", "type": "Secondary"}, {"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "nvd@nist.gov", "type": "Primary"}], "cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 6.9, "baseSeverity": "MEDIUM", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "NONE", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "NONE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "version": "4.0", "vulnAvailabilityImpact": "LOW", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "disclosure@vulncheck.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-35640", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-04-10T12:25:51.531666Z", "version": "2.0.3"}}]}, "published": "2026-04-09T22:16:33.507", "references": [{"source": "disclosure@vulncheck.com", "tags": ["Patch"], "url": "https://github.com/openclaw/openclaw/commit/5e8cb22176e9235e224be0bc530699261eb60e53"}, {"source": "disclosure@vulncheck.com", "tags": ["Vendor Advisory"], "url": "https://github.com/openclaw/openclaw/security/advisories/GHSA-3h52-cx59-c456"}, {"source": "disclosure@vulncheck.com", "tags": ["Third Party Advisory"], "url": "https://www.vulncheck.com/advisories/openclaw-denial-of-service-via-unauthenticated-webhook-request-parsing"}], "sourceIdentifier": "disclosure@vulncheck.com", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-696"}], "source": "disclosure@vulncheck.com", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,2026.3.25)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "2026.3.25"}}], "enrichment": {"confidence": 95.0, "confidence_source": "inferred", "scores": [{"score": 95.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "OpenClaw", "source": "cna", "vendor": "OpenClaw"}, "product": "openclaw", "vendor": "openclaw"}], "analysis": {"en": {"generated_at": "2026-04-09T22:38:08.582938+00:00", "value": {"mitigation_remediation": ["Apply the official patch or upgrade OpenClaw to version 2026.3.25 or later.", "If an immediate upgrade is not possible, restrict network access to the webhook endpoint or configure a firewall rule to limit traffic.", "As a temporary measure, disable webhook processing until the vulnerability can be remediated.", "Verify that signature validation occurs before any JSON parsing in custom deployments."], "summary": {"action": "Apply Patch", "impact": "Denial of Service"}, "threat_synthesis": {"affected_systems": "The affected product is OpenClaw, all releases prior to version 2026.3.25. The vendor is OpenClaw. Anyone running an older version is susceptible.", "description_and_impact": "The vulnerability exists because OpenClaw processes JSON payloads before verifying the webhook signature, allowing attackers to send large or malformed JSON data that causes high CPU and memory usage. This leads to a denial of service by exhausting server resources. The weakness is identified as CWE-696: Unchecked Input for Resource Exhaustion.", "risk_and_exploitability": "The CVSS score is 6.9, indicating medium severity, and the vulnerability is not listed in KEV. Exploitation requires only unauthenticated HTTP access to the webhook endpoint, which is typically exposed on the public network. Attackers can craft requests that trigger excessive parsing and consume CPU and memory, leading to service degradation or crash. The lack of authentication and the ability to send arbitrary JSON payloads make this a likely vector on exposed installations."}}}}, "created": "2026-04-10T08:37:40.268711+00:00", "updated": "2026-04-10T09:28:22.238555+00:00", "vendors": ["openclaw", "openclaw$PRODUCT$openclaw"]}