ReDoS in uri-template-lite URI.expand function

published 2022-08-24 4 y ago modified 2026-06-17 4 mo ago also GHSA-chw2-6c7r-37p7 , EUVD-2022-6538

cvss: 5.9; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.0%; EPSS 1.0% chance of exploitation in 30 days, percentile 62%
public exploits: 0; none known

An exponential ReDoS (Regular Expression Denial of Service) can be triggered in the uri-template-lite npm package, when an attacker is able to supply arbitrary input to the "URI.expand" method

Patch / fix

fixed in 2 links 1

npm uri-template-lite 22.9.0
uri-template-lite uri-template-lite 22.9.0

github.com/litejs/uri-template-lite@cbeec2b commit

Exploit prediction

0.99% chance of exploitation in the next 30 days, higher than 62% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

research.jfrog.com https://research.jfrog.com/vulnerabilities/uri-template-lite-redos-xray-211351/ referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.9	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
GitHub	3.1	5.9	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem	package	affected	fixed in
npm	uri-template-lite	<22.9.0	22.9.0

Affected products

uri-template-lite uri-template-lite

Classification

Weakness

CWE-1333 Inefficient Regular Expression Complexity
CWE-697 Incorrect Comparison

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary