CVE-2021-39933

Description

An issue has been discovered in GitLab CE/EE affecting all versions starting from 12.10 before 14.3.6, all versions starting from 14.4 before 14.4.4, all versions starting from 14.5 before 14.5.2. A regular expression used for handling user input (notes, comments, etc) was susceptible to catastrophic backtracking that could cause a DOS attack.

Category

4.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.24%
Third-Party Advisory gitlab.com Third-Party Advisory hackerone.com
Affected: GitLab GitLab
Published at:
Updated at:

References

Link Tags
https://gitlab.com/gitlab-org/gitlab/-/issues/340449 broken link
https://hackerone.com/reports/1320077 third party advisory permissions required
https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39933.json third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-39933?
CVE-2021-39933 has been scored as a medium severity vulnerability.
How to fix CVE-2021-39933?
To fix CVE-2021-39933, 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-2021-39933 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-39933 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-2021-39933?
CVE-2021-39933 affects GitLab GitLab.
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