Cyber Resilience

CVE-2021-39878

Medium

Published: 05 October 2021

Published
05 October 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 5.8 CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:N/A:N
EPSS Score 0.0019 40.1th percentile
Risk Priority 12 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-39878 is a medium-severity Cross-site Scripting (CWE-79) vulnerability in Gitlab Gitlab. Its CVSS base score is 5.8 (Medium).

Operationally, ranked at the 40.1th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

A stored Reflected Cross-Site Scripting vulnerability in the Jira integration in GitLab version 13.0 up to 14.3.1 allowed an attacker to execute arbitrary javascript code.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

gitlab
gitlab
13.0.0 — 14.1.7 · 13.0.0 — 14.1.7 · 14.2.0 — 14.2.5

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-79

Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.

addresses: CWE-79

Validates web inputs to reject script-related content that could produce XSS.

addresses: CWE-79

Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.

References