Two vulnerabilities have been reported in Samba, which can be exploited by malicious people to cause a DoS (Denial of Service).

1) An error exists in smbd within the ASN.1 parsing functionality. This can be exploited via specially crafted packets during authentication to spawn many new processes, which enter infinite loops.

Successful exploitation may exhaust all available memory resources.

2) An input validation error exists in nmbd within the "process_logon_packet()" function when processing mailslot packets. This can be exploited to crash the daemon via a specially crafted "SAM_UAS_CHANGE" request.

Successful exploitation requires that the daemon has been configured to process domain logons ("domain logons = yes" in smb.conf).

The vulnerabilities affect version 3.0.6 and prior.

Solution
Update to version 3.0.7.
Further details available to Secunia VIM customers

Provided and/or discovered by
Discovered by anonymous person and reported via iDEFENSE.

Original Advisory
Samba:
http://us3.samba.org/samba/history/3.0_DOS_sept04_announce.txt

iDEFENSE:
http://www.idefense.com/application/poi/display?id=138&type=vulnerabilities
http://www.idefense.com/application/poi/display?id=139&type=vulnerabilities

Deep Links
Links available to Secunia VIM customers