CVE-2018-1000831: k9mail K-9 Mail

Critical severity, CVSS 10.0. EPSS: 1.9% chance of exploitation in the next 30 days.

K9Mail version <= v5.600 contains a XML External Entity (XXE) vulnerability in WebDAV response parser that can result in Disclosure of confidential data, denial of service, SSRF, port scanning. This attack appear to be exploitable via malicious WebDAV server or intercept the reponse of a valid WebDAV server.

Affected products

• k9mail K-9 Mail: up to and including 5.600

Published 2018-12-20. Last modified 2026-06-17.