CVE-2021-39910
Status: ModifiedMedium (4.3)—
An issue has been discovered in GitLab CE/EE affecting all versions starting from 12.6 before 14.3.6, all versions starting from 14.4 before 14.4.4, all versions starting from 14.5 before 14.5.2. GitLab was vulnerable to HTML Injection through the Swagger UI feature.
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
- Base score: 4.3
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.99%
- Percentile among all scored CVEs: 61
- Score date: 10/8/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (1)
CWEs
- CWE-79
References
- https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39910.json
- https://gitlab.com/gitlab-org/gitlab/-/issues/325901
- https://hackerone.com/reports/1133656
- https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39910.json
- https://gitlab.com/gitlab-org/gitlab/-/issues/325901
- https://hackerone.com/reports/1133656
Raw JSON (NVD)
Show
{
"id": "CVE-2021-39910",
"cveTags": [],
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"authentication": "NONE",
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"published": "2021-12-13T16:15:08.740",
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"value": "An issue has been discovered in GitLab CE/EE affecting all versions starting from 12.6 before 14.3.6, all versions starting from 14.4 before 14.4.4, all versions starting from 14.5 before 14.5.2. GitLab was vulnerable to HTML Injection through the Swagger UI feature."
},
{
"lang": "es",
"value": "Se ha detectado un problema en GitLab CE/EE afectando a todas las versiones a partir de 12.6 anteriores a 14.3.6, todas las versiones a partir de 14.4 anteriores a 14.4.4, todas las versiones a partir de 14.5 anteriores a 14.5.2. GitLab era vulnerable a una inyección de HTML mediante la función Swagger UI"
}
],
"lastModified": "2026-06-17T04:04:24.557",
"configurations": [
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"nodes": [
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}