What is CVE-2018-20888?

CVE-2018-20888 is a medium-severity vulnerability in Cpanel, classified under Improper Authentication. CVSS score: 5.5/10. Published 2019-08-01.

How severe is CVE-2018-20888?

Medium severity. CVSS v3 base score is 5.5 out of 10.

Auth bypass in Cpanel

CVE-2018-20888

cPanel before 74.0.0 allows file modification in the context of the root account because of incorrect HTTP authentication (SEC-424).

Vulnerability class: Broken Authentication

Published 2019-08-01 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N.

EPSS exploit prediction

EPSS: 0.004 (26.9th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 27th percentile — 26.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Affected products

Cpanel

Weakness classification (CWE)

CWE-287 — Improper Authentication

References

documentation.cpanel.net/display/CL/74+Change+Log (Product, Release Notes)
news.cpanel.com/cpanel-tsr-2018-0004-full-disclosure/ (Vendor Advisory)

Frequently asked questions

What is CVE-2018-20888?: CVE-2018-20888 is a medium-severity vulnerability in Cpanel, classified under Improper Authentication. CVSS score: 5.5/10. Published 2019-08-01.
How severe is CVE-2018-20888?: Medium severity. CVSS v3 base score is 5.5 out of 10.