Vulnerability · Published Mar 10, 2026 · Assigned by GitHub_M

CVE-2026-30837Elysia has a string URL format redos

High 7.5

In plain English

A high-severity regular-expression denial of service in elysia from elysiajs. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 46% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.5High

Exploit odds (30 days)0.5%top 54.1% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Elysia is a Typescript framework for request validation, type inference, OpenAPI documentation and client-server communication. Prior to 1.4.26 , t.String({ format: 'url' }) is vulnerable to ReDoS. Repeating a partial url format (protocol and hostname) multiple times cause regex to slow down significantly. This vulnerability is fixed in 1.4.26.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
npm	elysia	1.4.26	GHSA-f45g-68q3-5w8x

Affected products (as reported)

Vendor	Product	Versions
elysiajs	elysia	< 1.4.26

Weakness: CWE-1333 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

https://github.com/elysiajs/elysia/security/advisories/GHSA-f45g-68q3-5w8x x_refsource_CONFIRM
https://github.com/EdamAme-x/elysia-poc-redos x_refsource_MISC