CVE-2003-1593 in NetWare
Summary
by MITRE
NWFTPD.nlm in the FTP server in Novell NetWare 6.0 before SP4 and 6.5 before SP1 does not enforce domain-name login restrictions, which allows remote attackers to bypass intended access control via an FTP connection.
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Analysis
by VulDB Data Team • 05/04/2026
The vulnerability described in CVE-2003-1593 represents a critical access control flaw in Novell NetWare 6.0 and 6.5 FTP server implementations. This issue specifically affects the NWFTPD.nlm module which handles file transfer protocol operations within the NetWare environment. The flaw stems from insufficient validation of domain name restrictions during the authentication process, creating a pathway for unauthorized access that directly undermines the intended security boundaries of the system. The vulnerability exists in versions prior to SP4 for NetWare 6.0 and SP1 for NetWare 6.5, indicating this was a known issue that required service pack updates to resolve.
The technical implementation of this vulnerability allows remote attackers to exploit the missing domain-name login restrictions by establishing an FTP connection to the affected NetWare server. When users attempt to authenticate through the FTP service, the system fails to properly verify that the connecting user belongs to the appropriate domain or meets the configured access control requirements. This authentication bypass occurs because the NWFTPD.nlm component does not enforce the domain restrictions that should normally be applied during the login process, enabling attackers to potentially gain access using credentials from unauthorized domains or without proper domain validation. The flaw operates at the protocol level where domain validation should occur during the initial connection handshake but instead allows unrestricted access regardless of domain membership.
The operational impact of this vulnerability extends beyond simple unauthorized access to potentially compromise the entire NetWare network infrastructure. Attackers could leverage this weakness to gain access to sensitive files, modify system configurations, or establish persistent access points within the network. The vulnerability particularly affects organizations that rely on domain-based access controls as their primary security mechanism, since the flaw essentially nullifies these protections for FTP services. Additionally, the remote nature of the attack means that unauthorized users can exploit this vulnerability from anywhere on the network without requiring physical access to the system, making it particularly dangerous for organizations with exposed FTP servers.
Organizations should implement immediate mitigations including applying the appropriate service packs for NetWare 6.0 SP4 and 6.5 SP1 to address the domain validation flaw. Network segmentation and firewall rules should be implemented to restrict access to FTP services to only trusted network segments. Additional monitoring should be enabled to detect unauthorized FTP connection attempts and unusual authentication patterns. The vulnerability aligns with CWE-284 which addresses improper access control in software implementations, and represents a clear violation of the principle of least privilege that should be enforced in all network services. From an ATT&CK framework perspective, this vulnerability maps to privilege escalation and initial access techniques, specifically targeting the T1110 credential access tactic where attackers attempt to bypass authentication mechanisms to gain system access. Organizations should also consider implementing additional authentication layers such as SSL/TLS encryption for FTP connections to add defense in depth against similar vulnerabilities.