CVE-2019-16769: Affected versions of serialize-javascript are vulnerable to Cross-site Scripting (XSS)

Severity: medium (CVSS 5.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-12-05 · updated 2026-06-17
Weakness: CWE-79

Description

The serialize-javascript npm package before version 2.1.1 is vulnerable to Cross-site Scripting (XSS). It does not properly mitigate against unsafe characters in serialized regular expressions. This vulnerability is not affected on Node.js environment since Node.js's implementation of RegExp.prototype.toString() backslash-escapes all forward slashes in regular expressions. If serialized data of regular expression objects are used in an environment other than Node.js, it is affected by this vulnerability.

Affected products

serialize-javascript: before 2.1.1 — fixed in 2.1.1
Npm Serialize-Javascript: before 2.1.1 — fixed in 2.1.1

How to fix

Upgrade to a fixed version: serialize-javascript 2.1.1; Npm Serialize-Javascript 2.1.1. Check the vendor advisory for mitigations.

References

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