The chain_reply function in process.c in smbd in Samba before 3.4.8 and 3.5.x before 3.5.2 allows remote attackers to cause a denial of service (NULL pointer dereference and process crash) via a Negotiate Protocol request with a certain 0x0003 field value followed by a Session Setup AndX request with a certain 0x8003 field value.
The reply_sesssetup_and_X_spnego function in sesssetup.c in smbd in Samba before 3.4.8 and 3.5.x before 3.5.2 allows remote attackers to trigger an out-of-bounds read, and cause a denial of service (process crash), via a \xff\xff security blob length in a Session Setup AndX request.
client/mount.cifs.c in mount.cifs in smbfs in Samba 3.4.5 and earlier does not verify that the (1) device name and (2) mountpoint strings are composed of valid characters, which allows local users to cause a denial of service (mtab corruption) via a crafted string.
Samba 3.4 before 3.4.2, 3.3 before 3.3.8, 3.2 before 3.2.15, and 3.0.12 through 3.0.36, as used in the SMB subsystem in Apple Mac OS X 10.5.8 when Windows File Sharing is enabled, Fedora 11, and other operating systems, does not properly handle errors in resolving pathnames, which allows remote authenticated users to bypass intended sharing restrictions, and read, create, or modify files, in certain circumstances involving user accounts that lack home directories.