Matthew Palmer discovered an underflow flaw in apr-util. An attacker could cause a denial of service via application crash in Apache using a crafted SVNMasterURI directive, .htaccess file, or when using mod_apreq2. Applications using libapreq2 are also affected. It was discovered that the XML parser did not properly handle entity expansion. A remote attacker could cause a denial of service via memory resource consumption by sending a crafted request to an Apache server configured to use mod_dav or mod_dav_svn. C. Michael Pilato discovered an off-by-one buffer overflow in apr-util when formatting certain strings. For big-endian machines , a remote attacker could cause a denial of service or information disclosure leak. All other architectures for Ubuntu are not considered to be at risk