CVE-2007-3207 in NetWare
Summary
by MITRE
Buffer overflow in the NFS mount daemon (XNFS.NLM) in Novell NetWare 6.5 SP6, and probably earlier, allows remote attackers to cause a denial of service (abend) via a long path in a mount request.
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Analysis
by VulDB Data Team • 11/27/2024
The vulnerability described in CVE-2007-3207 represents a critical buffer overflow condition within the Network File System (NFS) mount daemon component known as XNFS.NLM in Novell NetWare 6.5 Service Pack 6 and potentially earlier versions of the operating system. This flaw resides in the handling of mount requests where the daemon fails to properly validate the length of path parameters submitted by remote clients. The buffer overflow occurs when a malicious attacker crafts a mount request containing an excessively long path string that exceeds the allocated buffer space within the XNFS.NLM process. This condition falls under the Common Weakness Enumeration category CWE-121, which specifically addresses stack-based buffer overflow vulnerabilities that occur when insufficient bounds checking is performed on user-supplied data. The vulnerability manifests as a denial of service condition where the targeted NFS mount daemon process abnormally terminates, causing the system to become unresponsive to legitimate file access requests.
The technical exploitation of this vulnerability requires remote access to the NFS service and the ability to submit crafted mount requests with oversized path parameters. When the XNFS.NLM daemon processes such a malformed request, the buffer overflow corrupts adjacent memory locations, potentially leading to unpredictable behavior including process crashes, system instability, or complete service interruption. The attack vector is classified as remote since no local system access is required for exploitation, making it particularly dangerous in networked environments where NFS services are exposed to untrusted networks. The vulnerability demonstrates characteristics consistent with the ATT&CK framework's T1499.004 technique for network denial of service attacks, specifically targeting the availability of network services through the exploitation of software weaknesses. The impact extends beyond simple service disruption as it can affect business continuity and data accessibility for organizations relying on Novell NetWare file services.
Organizations affected by this vulnerability should implement immediate mitigations including applying the available security patches from Novell, which would typically involve updating to a patched version of NetWare that includes proper bounds checking for path parameters in mount requests. Network segmentation and firewall rules should be configured to restrict access to NFS services to only trusted hosts, reducing the attack surface. Additionally, monitoring systems should be deployed to detect unusual patterns in mount request sizes that might indicate exploitation attempts. The vulnerability highlights the importance of input validation and proper memory management in network services, particularly those handling user-supplied data in operating system components. Organizations should also consider implementing intrusion detection systems that can identify and alert on malformed NFS mount requests that exceed normal parameter lengths, providing an additional layer of defense against such attacks. The broader implications of this vulnerability underscore the need for comprehensive security testing of network services and the critical importance of maintaining up-to-date system patches to protect against known exploits.