XML External Entity (XXE) Injection Affecting expat package, versions <2.2.0-2+deb9u1

Note: Versions mentioned in the description apply only to the upstream expat package and not the expat package as distributed by Debian. See How to fix? for Debian:9 relevant fixed versions and status.

XML External Entity vulnerability in libexpat 2.2.0 and earlier (Expat XML Parser Library) allows attackers to put the parser in an infinite loop using a malformed external entity definition from an external DTD.

• https://security-tracker.debian.org/tracker/CVE-2017-9233
• https://support.apple.com/HT208112
• https://support.apple.com/HT208113
• https://support.apple.com/HT208115
• https://support.apple.com/HT208144
• https://github.com/libexpat/libexpat/blob/master/expat/Changes
• https://libexpat.github.io/doc/cve-2017-9233/
• https://support.f5.com/csp/article/K03244804
• https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-9233
• http://www.debian.org/security/2017/dsa-3898
• https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b@%3Cissues.bookkeeper.apache.org%3E
• https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4@%3Cissues.bookkeeper.apache.org%3E
• http://www.openwall.com/lists/oss-security/2017/06/17/7
• http://www.securityfocus.com/bid/99276
• http://www.securitytracker.com/id/1039427
• http://people.ubuntu.com/~ubuntu-security/cve/CVE-2017-9233
• https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3E
• https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3E