{"id":"UBUNTU-CVE-2016-0736","details":"In Apache HTTP Server versions 2.4.0 to 2.4.23, mod_session_crypto was encrypting its data/cookie using the configured ciphers with possibly either CBC or ECB modes of operation (AES256-CBC by default), hence no selectable or builtin authenticated encryption. This made it vulnerable to padding oracle attacks, particularly with CBC.","modified":"2026-04-22T10:26:57.981971Z","published":"2016-12-22T00:00:00Z","related":["USN-3279-1"],"upstream":["CVE-2016-0736"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2016-0736"},{"type":"REPORT","url":"https://lists.apache.org/thread.html/139862b41c0dfd5e6e00ad89c00119f9faf0dd41a2f927da9c9a4076@%3Cannounce.httpd.apache.org%3E"},{"type":"REPORT","url":"https://httpd.apache.org/security/vulnerabilities_24.html"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-3279-1"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2016-0736"}],"affected":[{"package":{"name":"apache2","ecosystem":"Ubuntu:14.04:LTS","purl":"pkg:deb/ubuntu/apache2@2.4.7-1ubuntu4.15?arch=source&distro=trusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.4.7-1ubuntu4.15"}]}],"versions":["2.4.6-2ubuntu2","2.4.6-2ubuntu3","2.4.6-2ubuntu4","2.4.7-1ubuntu1","2.4.7-1ubuntu2","2.4.7-1ubuntu3","2.4.7-1ubuntu4","2.4.7-1ubuntu4.1","2.4.7-1ubuntu4.4","2.4.7-1ubuntu4.5","2.4.7-1ubuntu4.6","2.4.7-1ubuntu4.7","2.4.7-1ubuntu4.8","2.4.7-1ubuntu4.9","2.4.7-1ubuntu4.10","2.4.7-1ubuntu4.11","2.4.7-1ubuntu4.13"],"ecosystem_specific":{"binaries":[{"binary_version":"2.4.7-1ubuntu4.15","binary_name":"apache2"},{"binary_version":"2.4.7-1ubuntu4.15","binary_name":"apache2-bin"},{"binary_version":"2.4.7-1ubuntu4.15","binary_name":"apache2-data"},{"binary_version":"2.4.7-1ubuntu4.15","binary_name":"apache2-mpm-event"},{"binary_version":"2.4.7-1ubuntu4.15","binary_name":"apache2-mpm-itk"},{"binary_version":"2.4.7-1ubuntu4.15","binary_name":"apache2-mpm-prefork"},{"binary_version":"2.4.7-1ubuntu4.15","binary_name":"apache2-mpm-worker"},{"binary_version":"2.4.7-1ubuntu4.15","binary_name":"apache2-suexec"},{"binary_version":"2.4.7-1ubuntu4.15","binary_name":"apache2-suexec-custom"},{"binary_version":"2.4.7-1ubuntu4.15","binary_name":"apache2-suexec-pristine"},{"binary_version":"2.4.7-1ubuntu4.15","binary_name":"apache2-utils"},{"binary_version":"2.4.7-1ubuntu4.15","binary_name":"apache2.2-bin"},{"binary_version":"1:2.4.7-1ubuntu4.15","binary_name":"libapache2-mod-macro"},{"binary_version":"1:2.4.7-1ubuntu4.15","binary_name":"libapache2-mod-proxy-html"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2016/UBUNTU-CVE-2016-0736.json"}},{"package":{"name":"apache2","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/apache2@2.4.18-2ubuntu3.2?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.4.18-2ubuntu3.2"}]}],"versions":["2.4.12-2ubuntu2","2.4.17-1ubuntu1","2.4.17-2ubuntu1","2.4.17-3ubuntu1","2.4.18-1ubuntu1","2.4.18-2ubuntu1","2.4.18-2ubuntu2","2.4.18-2ubuntu3","2.4.18-2ubuntu3.1"],"ecosystem_specific":{"binaries":[{"binary_version":"2.4.18-2ubuntu3.2","binary_name":"apache2"},{"binary_version":"2.4.18-2ubuntu3.2","binary_name":"apache2-bin"},{"binary_version":"2.4.18-2ubuntu3.2","binary_name":"apache2-data"},{"binary_version":"2.4.18-2ubuntu3.2","binary_name":"apache2-suexec-custom"},{"binary_version":"2.4.18-2ubuntu3.2","binary_name":"apache2-suexec-pristine"},{"binary_version":"2.4.18-2ubuntu3.2","binary_name":"apache2-utils"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2016/UBUNTU-CVE-2016-0736.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"},{"type":"Ubuntu","score":"medium"}]}