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GHSA-8796-gc9j-63rv

MediumCVSS 4.2 / 10
Published May 17, 2021·Last modified Mar 13, 2026
Affected Components(0)

No affected components available

Description

Impact

When uploading a file, the local file preview can lead to execution of scripts embedded in the uploaded file, but only after several user interactions to open the preview in a separate tab. This only impacts the local user while in the process of uploading. It cannot be exploited remotely or by other users.

Patches

This has been fixed by https://github.com/matrix-org/matrix-react-sdk/pull/5981, which is included in 3.21.0.

Workarounds

There are no known workarounds.

Risk Scores
Base Score
4.2

The vulnerability requires local access to the device to be exploited. It is difficult for an attacker to exploit this vulnerability and may require special conditions. An attacker needs basic access or low-level privileges. The attacker needs the user to perform some action, like clicking a link. The impact is confined to the system where the vulnerability exists. There is a low impact on the confidentiality of the information. There is a low impact on the integrity of the data. There is a low impact on the availability of the system.

Threat Intelligence
3.9

Limited exploitation activity has been observed. Close monitoring and planned remediation are recommended.

EPSS
0.37%

The exploit probability is very low. The vulnerability is unlikely to be exploited in the next 30 days.

Exploit
Not available

We did not find any exploit available. Neither in GitHub repositories nor in the Exploit-Database.

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