CVE-2004-0082 in Samba
Summary
by MITRE
The mksmbpasswd shell script (mksmbpasswd.sh) in Samba 3.0.0 and 3.0.1, when creating an account but marking it as disabled, may overwrite the user password with an uninitialized buffer, which could enable the account with a more easily guessable password.
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Analysis
by VulDB Data Team • 03/09/2021
The vulnerability described in CVE-2004-0082 resides within the mksmbpasswd shell script component of Samba versions 3.0.0 and 3.0.1, representing a critical security flaw that directly impacts user account creation and authentication mechanisms. This issue specifically manifests when administrators attempt to create new user accounts within the Samba environment while simultaneously marking them as disabled. The underlying technical implementation contains a buffer management error that creates a significant security risk through improper memory handling during password assignment processes.
The core technical flaw involves the mksmbpasswd.sh script's handling of uninitialized memory buffers during account creation procedures. When a user account is created with the disabled flag, the script fails to properly initialize the password buffer before assigning it to the new account. This memory management oversight results in the password field being populated with whatever data previously resided in the uninitialized memory locations, potentially containing remnants of previous password values or system data. This vulnerability directly maps to CWE-128, which addresses "Unsigned to Signed Conversion Error" and CWE-755, related to "Improper Handling of Exceptional Conditions" in software security contexts.
The operational impact of this vulnerability extends beyond simple password exposure, creating a substantial risk for Samba network environments where account management is critical for access control. An attacker who can manipulate the account creation process or gain access to the system where mksmbpasswd.sh is executed could potentially exploit this weakness to create accounts with predictable or weak passwords that are easily guessable. The vulnerability essentially allows for the creation of accounts that might inherit password values from previous operations, undermining the security model of user authentication and potentially enabling unauthorized access to network resources. This weakness particularly affects environments where Samba serves as a primary authentication server for file sharing and network access control.
Mitigation strategies for this vulnerability require immediate patching of affected Samba versions to either version 3.0.2 or later, where the memory management issue has been resolved. System administrators should also implement strict access controls over the mksmbpasswd.sh script and related account management functions, ensuring that only authorized personnel can execute these operations. Additional protective measures include monitoring account creation activities and implementing automated password strength checking mechanisms to detect potential weak passwords that might result from this vulnerability. The remediation process should also involve reviewing and updating security policies around account management procedures, particularly for disabled accounts where the risk of weak password inheritance is most pronounced. Organizations should also consider implementing multi-factor authentication mechanisms as additional layers of protection against potential exploitation of this type of memory management vulnerability.