homepage

From the announcement:
Expat 2.2.1 has been released. The change log has more details [2] than this mail, including commit SHA1s. For a quick overview of the security fixes and CVEs, we have:
 CVE-2017-9233 External entity infinite loop DoS [1]
 (CVE-2016-9063) Integer overflow (re-fix)
 n/a More integer overflow fixes
 (CVE-2016-0718) Fix regression bugs from 2.2.0's fix to CVE-2016-0718
 (CVE-2016-5300) Use os-specific entropy sources like getrandom
 n/a No longer leak parser pointer information
 n/a Prevent use of uninitialised variables
 n/a Add missing API parameter validation (NULL, len<0)
 (CVE-2012-0876) Counter hash flooding with SipHash
https://github.com/libexpat/libexpat/blob/R_2_2_1/expat/Changes
https://libexpat.github.io/doc/cve-2017-9233/