CVE-2026-31938: jsPDF is a library to generate PDFs in JavaScript. Prior to version 4.2.1, user control of the `options` argument of the `output` function allows atta...

Description

jsPDF is a library to generate PDFs in JavaScript. Prior to version 4.2.1, user control of the `options` argument of the `output` function allows attackers to inject arbitrary HTML (such as scripts) into the browser context the created PDF is opened in. The vulnerability can be exploited in the following scenario: the attacker provides values for the output options, for example via a web interface. These values are then passed unsanitized (automatically or semi-automatically) to the attack victim. The victim creates and opens a PDF with the attack vector using one of the vulnerable method overloads inside their browser. The attacker can thus inject scripts that run in the victims browser context and can extract or modify secrets from this context. The vulnerability has been fixed in jspdf@4.2.1. As a workaround, sanitize user input before passing it to the output method.

Metrics

CVSS 3.1

6.1/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

EPSS Probability

0.24%

15.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

Affected Software

Vendor	Product	Versions
Parall	Jspdf	< 4.2.1

References

https://github.com/parallax/jsPDF/commit/87a40bbd07e6b30575196370670b41f264aa78d7Patch
https://github.com/parallax/jsPDF/releases/tag/v4.2.1Product, Release Notes
https://github.com/parallax/jsPDF/security/advisories/GHSA-wfv2-pwc8-crg5Mitigation, Vendor Advisory

Timeline

Published: Mar 18, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-31938?

jsPDF is a library to generate PDFs in JavaScript. Prior to version 4.2.1, user control of the `options` argument of the `output` function allows attackers to inject arbitrary HTML (such as scripts) into the browser context the created PDF is opened in. The vulnerability can be exploited in the following scenario: the attacker provides values for the output options, for example via a web interface. These values are then passed unsanitized (automatically or semi-automatically) to the attack victim. The victim creates and opens a PDF with the attack vector using one of the vulnerable method overloads inside their browser. The attacker can thus inject scripts that run in the victims browser context and can extract or modify secrets from this context. The vulnerability has been fixed in jspdf@4.2.1. As a workaround, sanitize user input before passing it to the output method.

How severe is CVE-2026-31938?

CVE-2026-31938 has a CVSS score of 6.1/10 (MEDIUM severity). The EPSS model estimates a 0.24% probability of exploitation in the next 30 days.

How do I fix CVE-2026-31938?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.