What is CVE-2018-20664?

CVE-2018-20664 is a critical-severity vulnerability in Zohocorp Manageengine Adselfservice Plus, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 9.8/10. Published 2019-01-03.

How severe is CVE-2018-20664?

Critical severity. CVSS v3 base score is 9.8 out of 10.

XXE in Zohocorp Manageengine Adselfservice Plus

CVE-2018-20664

Zoho ManageEngine ADSelfService Plus 5.x before build 5701 has XXE via an uploaded product license.

Vulnerability class: XXE (XML External Entity)

Published 2019-01-03 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.081 (94.6th percentile), scored 2026-09-30.

Low probability of exploitation in the next 30 days, but still tracked. 95th percentile — 94.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.081 · newest: 0.081 · change: 0.000

Affected products

Zohocorp Manageengine Adselfservice Plus — versions 5.7

Weakness classification (CWE)

CWE-611 — Improper Restriction of XML External Entity Reference (XXE)

References

www.manageengine.com/products/self-service-password/release-notes.html (Release Notes, Vendor Advisory)
www.excellium-services.com/cert-xlm-advisory/cve-2018-20664/ (Third Party Advisory)

Frequently asked questions

What is CVE-2018-20664?: CVE-2018-20664 is a critical-severity vulnerability in Zohocorp Manageengine Adselfservice Plus, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 9.8/10. Published 2019-01-03.
How severe is CVE-2018-20664?: Critical severity. CVSS v3 base score is 9.8 out of 10.