CVE-2021-39887

Description

A stored Cross-Site Scripting vulnerability in the GitLab Flavored Markdown in GitLab CE/EE version 8.4 and above allowed an attacker to execute arbitrary JavaScript code on the victim's behalf.

Category

7.3
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.34%
Vendor Advisory gitlab.com
Affected: GitLab GitLab
Published at:
Updated at:

References

Link Tags
https://gitlab.com/gitlab-org/gitlab/-/issues/332903 broken link
https://hackerone.com/reports/1218174 third party advisory permissions required
https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39887.json vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-39887?
CVE-2021-39887 has been scored as a high severity vulnerability.
How to fix CVE-2021-39887?
To fix CVE-2021-39887, 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-2021-39887 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-39887 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-2021-39887?
CVE-2021-39887 affects GitLab GitLab.
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