8000 Unsafe media served inline on download endpoints · Advisory · t2bot/matrix-media-repo · GitHub
[go: up one dir, main page]
Skip to content

Unsafe media served inline on download endpoints

Moderate
turt2live published GHSA-5crw-6j7v-xc72 Sep 8, 2023

Package

matrix-media-repo (Binaries/Docker)

Affected versions

<1.3.0

Patched versions

1.3.0

Description

Impact

A malicious user can upload an SVG image containing JavaScript to their server. When matrix-media-repo is asked to serve that media via the /_matrix/media/(r0|v3)/download endpoint, it would be served with a Content-Disposition of inline. This can allow JavaScript to run in the browser if a client links to the /download endpoint directly.

Server operators which do not share a domain between matrix-media-repo and other services are not affected, but are encouraged to upgrade regardless.

Patches

77ec235 and bf8abdd fix the issue. Operators should upgrade to v1.3.0 as soon as possible.

Workarounds

The Content-Disposition header can be overridden by the reverse proxy in front of matrix-media-repo to always use attachment, defeating this issue at the cost of "worse" user experience when clicking download links.

References

https://developer.mozilla.org/en-US/docs/Web/SVG/Element/script

Severity

Moderate

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
None
Availability
None

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:N/A:N

CVE ID

CVE-2023-41318

Weaknesses

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. Learn more on MITRE.

Credits
0