CVE-2021-39906

Description

Improper validation of ipynb files in GitLab CE/EE version 13.5 and above allows an attacker to execute arbitrary JavaScript code on the victim's behalf.

Category

8.7
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 14.01% Top 10%
Vendor Advisory gitlab.com
Affected: GitLab GitLab
Published at:
Updated at:

References

Link Tags
https://gitlab.com/gitlab-org/gitlab/-/issues/341566 broken link
https://hackerone.com/reports/1347600 third party advisory permissions required
https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39906.json vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-39906?
CVE-2021-39906 has been scored as a high severity vulnerability.
How to fix CVE-2021-39906?
To fix CVE-2021-39906, 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-2021-39906 being actively exploited in the wild?
It is possible that CVE-2021-39906 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~14% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-39906?
CVE-2021-39906 affects GitLab GitLab.
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