CVE-2021-39906

mediumpriority · attend · 45EPSS 0.607 · 99 %ileEUUS

grimoire priorityP1 · Urgent

Exploitable?

—

no known exploitation

Likely / severe?

60.7% (99th) EPSS

CVSS 4.3 · medium

Is it mine?

9 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · nvd · osv

EPSS · scored 2026-10-26

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

Technical severity, 0–10. One row per scoring source.

8.7

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 4.3–8.7

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 8.6 · impact 2.9

v3.16.1mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 2.7

v3.18.7highCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:Nsecondary · ENISA EU

v3.18.7highCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:Nsecondary · cve@gitlab.comexploitability 2.3 · impact 5.8

v3.16.1mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:Hsecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-79USprimary

affected products (9)

Products and version ranges known to be affected.

GitLab GitLab13.5, → 14.2.6enisa_euvdEU
GitLab GitLab14.3, → 14.3.4enisa_euvdEU
GitLab GitLab14.4, → 14.4.1enisa_euvdEU
gitlab gitlab13.5.0 → 14.2.6nvdUScpe:2.3:a:gitlab:gitlab:*:*:*:*:*:*:*:*
gitlab gitlab14.3.0 → 14.3.4nvdUScpe:2.3:a:gitlab:gitlab:*:*:*:*:*:*:*:*
gitlab gitlab14.4.0 → 14.4.1nvdUScpe:2.3:a:gitlab:gitlab:*:*:*:*:*:*:*:*
Bitnami gitlab13.5.0 → 14.2.6osvUSpkg:bitnami/gitlab
Bitnami gitlab14.3.0 → 14.3.4osvUSpkg:bitnami/gitlab
Bitnami gitlab14.4.0 → 14.4.1osvUSpkg:bitnami/gitlab

advisories (1)

Vendor and ecosystem advisories describing this.

BIT-gitlab-2021-399062024-03-06vendor · osvUS
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.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd osv NVD CVE.org MITRE

published 2021-11-05modified 2026-06-17

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+52968 more

references (12)

External citations — patches, advisories, analysis.

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