What is CVE-2019-9658?

CVE-2019-9658 is a medium-severity vulnerability in Checkstyle, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 5.3/10. Published 2019-03-11.

How severe is CVE-2019-9658?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Is CVE-2019-9658 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

XXE in Checkstyle

CVE-2019-9658

Checkstyle before 8.18 loads external DTDs by default.

Vulnerability class: XXE (XML External Entity)

Published 2019-03-11 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.037 (89.3th percentile), scored 2026-10-02.

Low probability of exploitation in the next 30 days, but still tracked. 89th percentile — 89.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.037 · newest: 0.037 · change: 0.000

Affected products

Checkstyle
Debian Linux — versions 8.0
Fedoraproject Fedora — versions 28, 29

Weakness classification (CWE)

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

Public proof-of-concept exploits

ARPSyndicate/cvemon

References

github.com/checkstyle/checkstyle/pull/6476 (Third Party Advisory)
github.com/checkstyle/checkstyle/issues/6474 (Third Party Advisory)
github.com/checkstyle/checkstyle/issues/6478 (Third Party Advisory)
checkstyle.org/releasenotes.html (Release Notes, Vendor Advisory)
lists.apache.org/thread.html/7eea10e7be4c21060cb1e79f6524c6e6559ba833b1465cd287… (mailing-list)
lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
lists.debian.org/debian-lts-announce/2019/04/msg00029.html (mailing-list, Third Party Advisory)
lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
lists.apache.org/thread.html/a35a8ccb316d4c2340710f610cba8058e87d5376259b35ef3e… (mailing-list)

Frequently asked questions

What is CVE-2019-9658?: CVE-2019-9658 is a medium-severity vulnerability in Checkstyle, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 5.3/10. Published 2019-03-11.
How severe is CVE-2019-9658?: Medium severity. CVSS v3 base score is 5.3 out of 10.
Is CVE-2019-9658 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.