Executive brief
The matrix-react-sdk, a toolkit used to build Matrix-based chat applications, is vulnerable to a flaw that allows malicious messages to crash parts of the user interface. An attacker can send specially crafted messages that cause specific chat rooms or message tiles to stop rendering correctly for users. While the rest of the application remains functional, this can disrupt communications and prevent users from viewing certain content.
Technical details
A prototype pollution vulnerability (CWE-1321) exists in matrix-react-sdk prior to version 3.53.0. The vulnerability is triggered when the SDK processes incoming Matrix events containing specially crafted strings in specific key fields. An unauthenticated remote attacker can exploit this by sending malicious events to a room, leading to 'soft crashes' where specific room views or event tiles fail to render. This is caused by improper control of modifications to object prototype attributes during event processing. The issue is resolved in version 3.53.0.
Affected products
- Matrix.org matrix-react-sdk < 3.53.0
Timeline
- 2022-08-31: patched: Fixed in version 3.53.0
- 2023-03-28: disclosed: Public advisory published