CVE-2021-39880

Name: CVE-2021-39880
Creator: NVD / NIST
Published: 2021-10-05T15:15:07.727+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.5/10EPSS 1.33%

Last modified Jun 17, 2026

CVE-2021-39880 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. A Denial Of Service vulnerability in the apollo_upload_server Ruby gem in GitLab CE/EE all versions starting from 11.9 before 14.0.9, all versions starting from 14.1 before 14.1.4, and all versions starting from 14.2 before 14.2.2 allows an attacker to deny access to all users via specially crafted requests to the apollo_upload_server middleware.. EPSS estimates a 1.33% chance of exploitation in the next 30 days.

Description

A Denial Of Service vulnerability in the apollo_upload_server Ruby gem in GitLab CE/EE all versions starting from 11.9 before 14.0.9, all versions starting from 14.1 before 14.1.4, and all versions starting from 14.2 before 14.2.2 allows an attacker to deny access to all users via specially crafted requests to the apollo_upload_server middleware.

Metrics

CVSS 3.1

6.5/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

1.33%

67.4th percentile

Probability of exploitation in the next 30 days. Learn more

Affected Software

Vendor	Product	Versions
Gitlab	Gitlab	> 11.9.0, < 14.0.9
Gitlab	Gitlab	>= 11.9.0, < 14.0.9
Gitlab	Gitlab	> 14.1.0, < 14.1.4
Gitlab	Gitlab	>= 14.1.0, < 14.1.4
Gitlab	Gitlab	>= 14.2.0, < 14.2.2

References

https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39880.jsonVendor Advisory
https://gitlab.com/gitlab-org/gitlab/-/issues/330561Broken Link
https://hackerone.com/reports/1181284Permissions Required, Third Party Advisory
https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39880.jsonVendor Advisory
https://gitlab.com/gitlab-org/gitlab/-/issues/330561Broken Link
https://hackerone.com/reports/1181284Permissions Required, Third Party Advisory

Timeline

Published: Oct 5, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-39880?

How severe is CVE-2021-39880?

CVE-2021-39880 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 1.33% probability of exploitation in the next 30 days.

How do I fix CVE-2021-39880?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-39880?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST