How severe is CVE-2021-39880?

CVE-2021-39880 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-39880 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-39880?

CVE-2021-39880 primarily affects Gitlab. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-39880?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-39880 published?

CVE-2021-39880 was published on 2021-10-05 and last updated on 2026-06-17.

CVE-2021-39880

CVE-2021-39880 is a medium-severity vulnerability in Gitlab with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.0
EPSS exploit prediction: 1% (68th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Gitlab
Published: 2021-10-05
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2021-39880?: 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.
How severe is CVE-2021-39880?: CVE-2021-39880 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-39880 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-39880?: CVE-2021-39880 primarily affects Gitlab. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-39880?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-39880 published?: CVE-2021-39880 was published on 2021-10-05 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:gitlab:gitlab:*:*:*:*:community:*:*:*
cpe:2.3:a:gitlab:gitlab:*:*:*:*:enterprise:*:*:*

More vulnerabilities in Gitlab

CVE-2024-45409 — Critical (CVSS 10.0): The Ruby SAML library is for implementing the client side of a SAML authorization. Ruby-SAML in <= 12.2 and 1.13.0 <=…
CVE-2023-7028 — Critical (CVSS 10.0): An issue has been discovered in GitLab CE/EE affecting all versions from 16.1 prior to 16.1.6, 16.2 prior to 16.2.9,…
CVE-2023-2825 — Critical (CVSS 10.0): An issue has been discovered in GitLab CE/EE affecting only version 16.0.0. An unauthenticated malicious user can use a…
CVE-2022-0735 — Critical (CVSS 10.0): An issue has been discovered in GitLab CE/EE affecting all versions starting from 12.10 before 14.6.5, all versions…
CVE-2021-22205 — Critical (CVSS 10.0): An issue has been discovered in GitLab CE/EE affecting all versions starting from 11.9. GitLab was not properly…
CVE-2019-9174 — Critical (CVSS 10.0): An issue was discovered in GitLab Community and Enterprise Edition before 11.6.10, 11.7.x before 11.7.6, and 11.8.x…

All CVEs affecting Gitlab →