Headline
GHSA-c9vx-2g7w-rp65: matrix-react-sdk vulnerable to XSS in Export Chat feature
Description
The Export Chat feature includes certain attacker-controlled elements in the generated document without sufficient escaping, leading to stored XSS.
Impact
Since the Export Chat feature generates a separate document, an attacker can only inject code run from the null origin, restricting the impact.
However, the attacker can still potentially use the XSS to leak message contents. A malicious homeserver is a potential attacker since the affected inputs are controllable server-side.
Patches
Has the problem been patched? What versions should users upgrade to?
Workarounds
None, other than not using the Export Chat feature.
References
Are there any links users can visit to find out more?
Description
The Export Chat feature includes certain attacker-controlled elements in the generated document without sufficient escaping, leading to stored XSS.
Impact
Since the Export Chat feature generates a separate document, an attacker can only inject code run from the null origin, restricting the impact.
However, the attacker can still potentially use the XSS to leak message contents. A malicious homeserver is a potential attacker since the affected inputs are controllable server-side.
Patches
Has the problem been patched? What versions should users upgrade to?
Workarounds
None, other than not using the Export Chat feature.
References
Are there any links users can visit to find out more?
References
- GHSA-c9vx-2g7w-rp65
- matrix-org/matrix-react-sdk@22fcd34
- https://github.com/matrix-org/matrix-react-sdk/releases/tag/v3.76.0
Related news
matrix-react-sdk is a react-based SDK for inserting a Matrix chat/voip client into a web page. The Export Chat feature includes certain attacker-controlled elements in the generated document without sufficient escaping, leading to stored Cross site scripting (XSS). Since the Export Chat feature generates a separate document, an attacker can only inject code run from the `null` origin, restricting the impact. However, the attacker can still potentially use the XSS to leak message contents. A malicious homeserver is a potential attacker since the affected inputs are controllable server-side. This issue has been addressed in commit `22fcd34c60` which is included in release version 3.76.0. Users are advised to upgrade. The only known workaround for this issue is to disable or to not use the Export Chat feature.