CVE-2021-39906
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.
Does this matter?
EPSS puts the probability of exploitation in the next 30 days at 60.7%, higher than 99% of all known CVEs. Patch or mitigate before the next change window.
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.
- CVSS 3.1
- 6.1 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
- EPSS
- 60.73% probability · 99th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-79
- Affected
- gitlab/gitlab
- Source
- cve@gitlab.com
EPSS 60.7% since 3 November 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39906.jsonVendor Advisory
- https://gitlab.com/gitlab-org/gitlab/-/issues/341566Broken Link
- https://hackerone.com/reports/1347600Permissions Required, Third Party Advisory
- https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39906.jsonVendor Advisory
- https://gitlab.com/gitlab-org/gitlab/-/issues/341566Broken Link
- https://hackerone.com/reports/1347600Permissions Required, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.