Title: Microsoft Windows 9x / Me Share Level Password Bypass Vulnerability
Severity: HIGH
Description:
Share level password protection for the File and Print Sharing service in Windows 95/98/ME can be bypassed.
Share level access provides peer to peer networking capabilities in the Windows 9x/ME environment. It depends on password protection in order to grant or deny access to resources. Due to a flaw in the implementation of File and Print Sharing security, a remote intruder could access share level protected resources without entering a complete password by programatically modifying the data length of the password.
The flaw is due to the NetBIOS implementation in the password verification scheme share level access utilizes.
The password length is compared to the length of data sent during the password verification process. If the password was programatically set to be 1 byte, then only the first byte would be verified. If a remote attacker was able to correctly guess the value of the first byte of the password on the target machine, access would be granted to the share level protected resource.
Windows 9x remote administration is also affected by this vulnerability because it uses the same authentication scheme.
Successful exploitation of this vulnerability could lead to the retrieval, modification, addition, and deletion of files residing on a file or print share.
Affected Products:
- Microsoft Windows 95
- Microsoft Windows 98
- Microsoft Windows 98SE
- Microsoft Windows ME
References:
- Microsoft: Frequently Asked Questions: Microsoft Security Bulletin (MS00-072)
- Microsoft: Q273991: Patch Available for "Share Level Password" Vulnerability
- Nsfocus: Microsoft Windows 9x NETBIOS password verification vulnerability
Juniper Networks provides this content via a wide variety of sources and production methods. If notified of errors or omissions in the content of this page, Juniper Networks, at its discretion, will modify or remove the page or leave the content as is, depending on various factors including but not limited to the reputation and authority of the party providing the notification. Please use the contact information displayed elsewhere on this page to report any errors or omissions regarding the content on this page.
