What is CVE-2018-20498?

CVE-2018-20498 is a medium-severity vulnerability in GitLab, classified under Incorrect Authorization. CVSS score: 4.3/10. Published 2019-12-30.

How severe is CVE-2018-20498?

Medium severity. CVSS v3 base score is 4.3 out of 10.

Auth bypass in GitLab

CVE-2018-20498

An issue was discovered in GitLab Community and Enterprise Edition before 11.4.13, 11.5.x before 11.5.6, and 11.6.x before 11.6.1. It has Incorrect Access Control.

Vulnerability class: Broken Access Control

Published 2019-12-30 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.007 (49.5th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 49th percentile — 49.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: 0.000

Affected products

GitLab

Weakness classification (CWE)

CWE-863 — Incorrect Authorization

References

about.gitlab.com/2018/12/31/security-release-gitlab-11-dot-6-dot-1-released/ (Vendor Advisory)
gitlab.com/gitlab-org/gitlab-ce/issues/50995 (Vendor Advisory)

Frequently asked questions

What is CVE-2018-20498?: CVE-2018-20498 is a medium-severity vulnerability in GitLab, classified under Incorrect Authorization. CVSS score: 4.3/10. Published 2019-12-30.
How severe is CVE-2018-20498?: Medium severity. CVSS v3 base score is 4.3 out of 10.