CVE-2021-39917
An issue has been discovered in GitLab CE/EE affecting all versions starting from 12.9 before 14...
An issue has been discovered in GitLab CE/EE affecting all versions starting from 12.9 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 related to quick actions features was susceptible to catastrophic backtracking that could cause a DOS attack.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
An issue has been discovered in GitLab CE/EE affecting all versions starting from 12.9 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 related to quick actions features was susceptible to catastrophic backtracking that could cause a DOS attack.
- Record
CVE-2021-39917- CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L - Updated
- 2026-11-02
EUVDEUVD-2021-26273
An issue has been discovered in GitLab CE/EE affecting all versions starting from 12.9 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 related to quick actions features was susceptible to catastrophic backtracking that could cause a DOS attack.
- Record
EUVD-2021-26273- CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-86j2-r9c9-2h84 No score
An issue has been discovered in GitLab CE/EE affecting all versions starting from 12.9 before 14...
An issue has been discovered in GitLab CE/EE affecting all versions starting from 12.9 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 related to quick actions features was susceptible to catastrophic backtracking that could cause a DOS attack.
- Record
GHSA-86j2-r9c9-2h84- Weakness
- CWE-697
- Updated
- 2026-11-02
NVD
An issue has been discovered in GitLab CE/EE affecting all versions starting from 12.9 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 related to quick actions features was susceptible to catastrophic backtracking that could cause a DOS attack.
- Record
CVE-2021-39917- CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L - CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - CVSS 2.0
- 4.0 Medium
AV:N/AC:L/Au:S/C:N/I:N/A:P - Weakness
- CWE-697
- Updated
- 2026-11-02
OSV
An issue has been discovered in GitLab CE/EE affecting all versions starting from 12.9 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 related to quick actions features was susceptible to catastrophic backtracking that could cause a DOS attack.
- Record
CVE-2021-39917- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2021-39917
An issue has been discovered in GitLab CE/EE affecting all versions starting from 12.9 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 related to quick actions features was susceptible to catastrophic backtracking that could cause a DOS attack.
- Record
UBUNTU-CVE-2021-39917- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L - Updated
- 2026-11-02
OSVBIT-gitlab-2021-39917 No score
An issue has been discovered in GitLab CE/EE affecting all versions starting from 12.9 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 related to quick actions features was susceptible to catastrophic backtracking that could cause a DOS attack.
- Record
BIT-gitlab-2021-39917- Updated
- 2026-11-02
Affected products
Affected packages
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-2021-39917 is a medium vulnerability (CVSS 4.3) in Gitlab, published December 13, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.37%, the 72nd percentile. Fixed in gitlab 14.3.6.