CVE-2021-32622
File upload local preview can run embedded scripts after user interaction
Matrix-React-SDK is a react-based SDK for inserting a Matrix chat/voip client into a web page. Before version 3.21.0, when uploading a file, the local file preview can lead to execution of scripts embedded in the uploaded file. This can only occur 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. This vulnerability is patched in version 3.21.0.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- High
- Privileges needed
- Low
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
File upload local preview can run embedded scripts after user interaction
Matrix-React-SDK is a react-based SDK for inserting a Matrix chat/voip client into a web page. Before version 3.21.0, when uploading a file, the local file preview can lead to execution of scripts embedded in the uploaded file. This can only occur 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. This vulnerability is patched in version 3.21.0.
- Record
CVE-2021-32622- CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:L - Weakness
- CWE-74
- Updated
- 2026-11-02
EUVDEUVD-2022-0961
Matrix-React-SDK is a react-based SDK for inserting a Matrix chat/voip client into a web page. Before version 3.21.0, when uploading a file, the local file preview can lead to execution of scripts embedded in the uploaded file. This can only occur 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. This vulnerability is patched in version 3.21.0.
- Record
EUVD-2022-0961- CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:L - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-8796-gc9j-63rv
File upload local preview can run embedded scripts after user interaction
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.
- Record
GHSA-8796-gc9j-63rv- CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:L - Weakness
- CWE-74
- Updated
- 2026-11-02
GitHub AdvisoriesGHSA-cg57-p69r-3m7p
Improper file handling in matrix-react-sdk
Matrix-React-SDK is a react-based SDK for inserting a Matrix chat/voip client into a web page. Before version 3.21.0, when uploading a file, the local file preview can lead to execution of scripts embedded in the uploaded file. This can only occur 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. This vulnerability is patched in version 3.21.0.
- Record
GHSA-cg57-p69r-3m7p- CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:L - Weakness
- CWE-74, CWE-434
- Updated
- 2026-11-02
NVD
Matrix-React-SDK is a react-based SDK for inserting a Matrix chat/voip client into a web page. Before version 3.21.0, when uploading a file, the local file preview can lead to execution of scripts embedded in the uploaded file. This can only occur 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. This vulnerability is patched in version 3.21.0.
- Record
CVE-2021-32622- CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:L - CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - CVSS 2.0
- 4.4 Medium
AV:L/AC:M/Au:N/C:P/I:P/A:P - Weakness
- CWE-74, CWE-434
- Updated
- 2026-11-02
OSV
Matrix-React-SDK is a react-based SDK for inserting a Matrix chat/voip client into a web page. Before version 3.21.0, when uploading a file, the local file preview can lead to execution of scripts embedded in the uploaded file. This can only occur 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. This vulnerability is patched in version 3.21.0.
- Record
CVE-2021-32622- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVGHSA-8796-gc9j-63rv
File upload local preview can run embedded scripts after user interaction
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.
- Record
GHSA-8796-gc9j-63rv- CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:L - Weakness
- CWE-74
- Updated
- 2026-11-02
OSVGHSA-cg57-p69r-3m7p
Improper file handling in matrix-react-sdk
Matrix-React-SDK is a react-based SDK for inserting a Matrix chat/voip client into a web page. Before version 3.21.0, when uploading a file, the local file preview can lead to execution of scripts embedded in the uploaded file. This can only occur 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. This vulnerability is patched in version 3.21.0.
- Record
GHSA-cg57-p69r-3m7p- CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:L - Weakness
- CWE-434, CWE-74
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
matrix-react-sdknpm |
before 3.21.0 | 3.21.0 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-32622 is a medium vulnerability (CVSS 4.2) in Matrix-org Matrix-react-sdk, published May 17, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.37%, the 31st percentile. Fixed in matrix-react-sdk 3.21.0.
References
github.com/matrix-org/matrix-react-sdk/security/advisories/GHSA-8796-gc9j-63rv
nvd.nist.gov/vuln/detail/CVE-2021-32622
npmjs.com/package/matrix-react-sdk