It was found that samba before 4.4.16, 4.5.x before 4.5.14, and 4.6.x before 4.6.8 did not enforce "SMB signing" when certain configuration options were enabled. A remote attacker could launch a man-in-the-middle attack and retrieve information in plain-text.
An information leak flaw was found in the way SMB1 protocol was implemented by Samba before 4.4.16, 4.5.x before 4.5.14, and 4.6.x before 4.6.8. A malicious client could use this flaw to dump server memory contents to a file on the samba share or to a shared printer, though the exact area of server memory cannot be controlled by the attacker.
All versions of Samba from 4.0.0 onwards are vulnerable to a denial of service attack when the RPC spoolss service is configured to be run as an external daemon. Missing input sanitization checks on some of the input parameters to spoolss RPC calls could cause the print spooler service to crash.
On a Samba 4 AD DC the LDAP server in all versions of Samba from 4.0.0 onwards incorrectly validates permissions to modify passwords over LDAP allowing authenticated users to change any other users' passwords, including administrative users and privileged service accounts (eg Domain Controllers).
Samba before versions 4.6.1, 4.5.7 and 4.4.11 are vulnerable to a malicious client using a symlink race to allow access to areas of the server file system not exported under the share definition.
Heimdal before 7.4 allows remote attackers to impersonate services with Orpheus' Lyre attacks because it obtains service-principal names in a way that violates the Kerberos 5 protocol specification. In _krb5_extract_ticket() the KDC-REP service name must be obtained from the encrypted version stored in 'enc_part' instead of the unencrypted version stored in 'ticket'. Use of the unencrypted version provides an opportunity for successful server impersonation and other attacks. NOTE: this CVE is only for Heimdal and other products that embed Heimdal code; it does not apply to other instances in which this part of the Kerberos 5 protocol specification is violated.
smbd in Samba before 4.4.10 and 4.5.x before 4.5.6 has a denial of service vulnerability (fd_open_atomic infinite loop with high CPU usage and memory consumption) due to wrongly handling dangling symlinks.
Samba since version 3.5.0 and before 4.6.4, 4.5.10 and 4.4.14 is vulnerable to remote code execution vulnerability, allowing a malicious client to upload a shared library to a writable share, and then cause the server to load and execute it.