Vulnerability advisory

GHSA-xvg8-m4x3-w6xr

matrix-js-sdk has insufficient MXC URI validation which allows client-side path traversal

Published Nov 12, 2024Updated Nov 4, 2025OSV record ↗

Also known as CVE-2024-50336

Severity

CVSS 4.0CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N

Affected versions

matrix-js-sdk npm

All matrix-js-sdk advisories →

Affected	Fixed in
All versions before 34.11.1	`34.11.1`Advisories →

Description

Summary

matrix-js-sdk before 34.11.0 is vulnerable to client-side path traversal via crafted MXC URIs. A malicious room member can trigger clients based on the matrix-js-sdk to issue arbitrary authenticated GET requests to the client's homeserver.

Details

The Matrix specification demands homeservers to perform validation of the server-name and media-id components of MXC URIs with the intent to prevent path traversal. However, it is not mentioned that a similar check must also be performed on the client to prevent client-side path traversal. matrix-js-sdk fails to perform this validation.