Vulnerability identifier: #VU54093

Vulnerability risk: Low

CVSSv3.1: 6.3 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-22220

CWE-ID: CWE-79

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Gitlab Community Edition
Universal components / Libraries / Software for developers
GitLab Enterprise Edition
Universal components / Libraries / Software for developers

Vendor: GitLab, Inc

Description

The disclosed vulnerability allows a remote attacker to perform cross-site scripting (XSS) attacks.

The vulnerability exists due to insufficient sanitization of user-supplied data in blob viewer of notebooks. A remote attacker can inject and execute arbitrary HTML and script code in user's browser in context of vulnerable website.

Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Gitlab Community Edition: 13.10.0 - 13.12.1

GitLab Enterprise Edition: 13.10.0 - 13.12.0

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External links
http://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-22220.json
http://hackerone.com/reports/1060114
http://gitlab.com/gitlab-org/gitlab/-/issues/294128

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.