XML External Entity (XXE) vulnerability in bw-calendar-engine

published 2018-12-20 7y ago modified 2026-06-17 4mo ago also GHSA-xmvg-w4f9-99r7 , EUVD-2018-0824

cvss: 9.0; version 3.0, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 1.1%; EPSS 1.1% chance of exploitation in 30 days, percentile 66%
public exploits: 0; none known

bw-calendar-engine version <= bw-calendar-engine-3.12.0 contains a XML External Entity (XXE) vulnerability in IscheduleClient XML Parser that can result in Disclosure of confidential data, denial of service, SSRF, port scanning. This attack appear to be exploitable via Man in the Middle or malicious server.

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Exploit prediction

1.13% chance of exploitation in the next 30 days, higher than 66% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
NVD	3.0	9.0	CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
NVD	2.0	6.8	AV:N/AC:M/Au:N/C:P/I:P/A:P
GitHub	3.0	9.0	CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H

Affected packages

ecosystem	package	affected	fixed in
maven	org.bedework.caleng:bw-calendar-engine	<=3.12.2	no fix listed

Classification

Weakness

CWE-611 Improper Restriction of XML External Entity Reference

References

github.com /Bedework/bw-calendar-engine/issues/3
web, third-party-advisory
0dd.zone /2018/10/28/bw-calendar-engine-XXE-MitM/
third-party-advisory
nvd.nist.gov /vuln/detail/CVE-2018-1000836
advisory
0dd.zone /2018/10/28/bw-calendar-engine-XXE-MitM
web
github.com /Bedework/bw-calendar-engine
package
github.com /advisories/GHSA-xmvg-w4f9-99r7
advisory

Sources

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