XXE in Apache Commons Jelly

CVE-2017-12621

During Jelly (xml) file parsing with Apache Xerces, if a custom doctype entity is declared with a "SYSTEM" entity with a URL and that entity is used in the body of the Jelly file, during parser instantiation the parser will attempt to connect to said URL. This could lead to XML External Entity (XXE) attacks in Apache Commons Jelly before 1.0.1.

Vulnerability class: XXE (XML External Entity)

EPSS: 0.085 (94.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2017-12621?
CVE-2017-12621 is a critical-severity vulnerability in Apache Commons Jelly, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 9.8/10. Published 2017-09-28.
How severe is CVE-2017-12621?
Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2017-12621 known to be exploited?
3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.