CVE-2021-21320

User content sandbox can be confused into opening arbitrary documents

Description

matrix-react-sdk is an npm package which is a Matrix SDK for React Javascript. In matrix-react-sdk before version 3.15.0, the user content sandbox can be abused to trick users into opening unexpected documents. The content is opened with a `blob` origin that cannot access Matrix user data, so messages and secrets are not at risk. This has been fixed in version 3.15.0.

Category

2.6
CVSS
Severity: Low
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.18%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory npmjs.com
Affected: matrix-org matrix-react-sdk
Published at:
Updated at:

References

Link Tags
https://github.com/matrix-org/matrix-react-sdk/security/advisories/GHSA-52mq-6jcv-j79x third party advisory
https://github.com/matrix-org/matrix-react-sdk/pull/5657 third party advisory patch
https://github.com/matrix-org/matrix-react-sdk/commit/b386f0c73b95ecbb6ea7f8f79c6ff5171a8dedd1 third party advisory patch
https://www.npmjs.com/package/matrix-react-sdk third party advisory product

Frequently Asked Questions

What is the severity of CVE-2021-21320?
CVE-2021-21320 has been scored as a low severity vulnerability.
How to fix CVE-2021-21320?
To fix CVE-2021-21320, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-21320 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-21320 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-21320?
CVE-2021-21320 affects matrix-org matrix-react-sdk.
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