Samba is an open-source implementation of the Server Message Block (SMB) orCommon Internet File System (CIFS) protocol, which allows PC-compatiblemachines to share files, printers, and other information.A denial of service flaw was found in the LDAP server provided by the AD DCin the Samba process daemon. A remote attacker could exploit this flaw bysending a specially crafted packet, which could cause the server to consumean excessive amount of memory and crash. (CVE-2015-7540)Multiple buffer over-read flaws were found in the way Samba handledmalformed inputs in certain encodings. An authenticated, remote attackercould possibly use these flaws to disclose portions of the server memory.(CVE-2015-5330)A man-in-the-middle vulnerability was found in the way "connection signing"was implemented by Samba. A remote attacker could use this flaw todowngrade an existing Samba client connection and force the use of plaintext. (CVE-2015-5296)A missing access control flaw was found in Samba. A remote, authenticatedattacker could use this flaw to view the current snapshot on a Samba share,despite not having DIRECTORY_LIST access rights. (CVE-2015-5299)An access flaw was found in the way Samba verified symbolic links whencreating new files on a Samba share. A remote attacker could exploit thisflaw to gain access to files outside of Samba's share path. (CVE-2015-5252)Red Hat would like to thank the Samba project for reporting these issues.Upstream acknowledges Stefan Metzmacher of the Samba Team and Sernet.de asthe original reporters of CVE-2015-5296, firstname.lastname@example.org as the originalreporter of CVE-2015-5299, Jan "Yenya" Kasprzak and the Computer SystemsUnit team at Faculty of Informatics, Masaryk University as the originalreporters of CVE-2015-5252 flaws, and Douglas Bagnall as the originalreporter of CVE-2015-5330.All samba4 users are advised to upgrade to these updated packages, whichcontain backported patches to correct these issues. After installing thisupdate, the smb service will be restarted automatically.