CVE-2026-110725
Received
Received - Intake
URI Parsing Issue in fast-uri Leading to XSS
Vulnerability report for CVE-2026-110725, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-10-20
Last updated on: 2026-10-20
Assigner: openjs
Description
Description
fast-uri is a dependency-free RFC 3986 URI parser and serializer for Node.js. In versions before 2.4.8, from 3.0.0 through 3.1.8, and from 4.0.0 through 4.2.2, when serialize(), normalize(), or resolve() are called with the non-default option reference set to suffix on a reference that has no authority, the emitted relative reference can contain a bare colon in its first path segment without escaping it, even though RFC 3986 forbids that because it makes the string reparse as an absolute URI with a scheme. An application that serializes or normalizes a relative reference with the suffix option and then treats the result as a URI can turn inert input into a live javascript, data, or vbscript URL, a cross-site scripting vector, and the equal() comparison can conflate a scheme-bearing reference with a relative one. Exposure is limited to applications using the non-default suffix reference option. The issue is fixed in fast-uri 2.4.8, 3.1.9, and 4.2.3, and users should upgrade to one of these versions or later. As a workaround, avoid the suffix reference option on untrusted input, or percent-encode a colon in the first path segment of the result before treating it as a URI.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| fast-uri | fast-uri | 0 |
| fast-uri | fast-uri | 3.0.0 |
| fast-uri | fast-uri | 4.0.0 |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-41 | The product is vulnerable to file system contents disclosure through path equivalence. Path equivalence involves the use of special characters in file and directory names. The associated manipulations are intended to generate multiple names for the same object. |
| CWE-116 | The product prepares a structured message for communication with another component, but encoding or escaping of the data is either missing or done incorrectly. As a result, the intended structure of the message is not preserved. |
