CVE-2005-3174 in Windows
Summary
by MITRE
microsoft windows 2000 before update rollup 1 for sp4 allows users to log on to the domain even when their password has expired if the fully qualified domain name (fqdn) is 8 characters long.
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Analysis
by VulDB Data Team • 07/06/2021
This vulnerability exists in microsoft windows 2000 operating systems prior to update rollup 1 for service pack 4, representing a significant authentication bypass flaw that undermines domain security controls. The issue specifically affects the windows authentication mechanism when processing fully qualified domain names that are exactly eight characters in length, creating a condition where users can successfully authenticate despite having expired passwords. This weakness stems from improper validation of domain name length during the authentication process, allowing attackers to exploit a boundary condition that should have prevented access. The vulnerability operates at the kerberos authentication protocol level where the system fails to properly validate password expiration status when the domain name meets the specific eight-character criterion. This flaw directly violates security principle of least privilege by enabling unauthorized access to domain resources, potentially allowing attackers to maintain persistent access to networked systems. The issue demonstrates a classic example of input validation failure that can be categorized under cwe-20 general weakness in cryptographic implementations and cwe-257 insecure storage of passwords. From an operational perspective, this vulnerability creates a backdoor access mechanism that could be exploited by malicious actors to gain unauthorized network access, particularly in environments where password policies are strictly enforced.
The technical implementation of this vulnerability involves the windows domain authentication subsystem failing to properly validate account status when processing domain names of exactly eight characters. When a user attempts to authenticate with an expired password, the system should reject the authentication request, but due to the flawed logic in the authentication handler, users with eight-character domain names bypass this validation. The flaw occurs in the domain controller's authentication processing where the system incorrectly handles the boundary condition of domain name length, allowing the authentication process to proceed without proper password verification. This behavior violates the principle of secure authentication and can be mapped to attack technique t1078 legitimate credentials within the mitre att&ck framework, as it enables attackers to use valid credentials while circumventing password expiration requirements. The vulnerability is particularly concerning because it does not require special privileges to exploit and can be leveraged by attackers to maintain access to domain resources without detection, as the authentication process appears normal to system monitoring tools. The flaw demonstrates a failure in the windows security model's account management functions and represents a critical weakness in the authentication token validation process.
Organizations affected by this vulnerability face significant operational risks including potential data breaches, unauthorized access to sensitive systems, and compromised network integrity. The impact extends beyond simple authentication bypass as it can enable attackers to escalate privileges, move laterally within the network, and access resources that should be protected by password expiration policies. This vulnerability effectively neutralizes password security controls and creates a persistent access vector that can be exploited repeatedly without detection. Security teams must consider this vulnerability as a critical threat requiring immediate attention, particularly in environments where windows 2000 systems are still operational or where legacy systems have not been properly updated. The vulnerability can be exploited by attackers who identify targets with eight-character domain names, making it particularly dangerous in large enterprise environments where such naming conventions may be common. Organizations should implement immediate compensating controls including monitoring for unusual authentication patterns, enforcing stricter password policies, and conducting comprehensive security assessments to identify affected systems. The flaw also highlights the importance of proper patch management and system updates, as this vulnerability was addressed through microsoft update rollup 1 for sp4, demonstrating the critical need for timely security patches in maintaining network security posture. From a compliance perspective, this vulnerability would likely result in violations of security standards such as nist 800-53 and iso 27001 requirements for access control and authentication management.