Samba is an open-source implementation of the Server Message Block or Common Internet File System protocol, which allows PC-compatible machines to share files, printers, and other information. A heap-based buffer overflow flaw was found in the DCE-RPC client code in Samba. A specially crafted DCE-RPC packet could cause various Samba programs to crash or, possibly, execute arbitrary code when parsed. A malicious or compromised Active Directory Domain Controller could use this flaw to compromise the winbindd daemon running with root privileges. Red Hat would like to thank the Samba project for reporting this issue. Upstream acknowledges Stefan Metzmacher and Michael Adam of SerNet as the original reporters of this issue. All users of Samba are advised to upgrade to these updated packages, which contain a backported patch to correct this issue. After installing this update, the smb service will be restarted automatically.