CVE-2010-4327 in eDirectory
Summary
by MITRE
Unspecified vulnerability in the NCP service in Novell eDirectory 8.8.5 before 8.8.5.6 and 8.8.6 before 8.8.6.2 allows remote attackers to cause a denial of service (hang) via a malformed FileSetLock request to port 524.
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Analysis
by VulDB Data Team • 10/16/2021
The vulnerability described in CVE-2010-4327 represents a critical denial of service weakness within Novell eDirectory's NCP service implementation. This issue affects specific versions of the directory service software, particularly those in the 8.8.5 and 8.8.6 release series before their respective patch levels. The vulnerability manifests when the NCP service receives a malformed FileSetLock request on the standard port 524, which is used for Novell's NetWare Core Protocol communication. This particular service port serves as a crucial communication channel for directory services and network resource management within Novell environments, making it a significant target for attackers seeking to disrupt network operations.
The technical flaw stems from inadequate input validation within the NCP service's processing of FileSetLock requests. When a remote attacker crafts and sends a malformed request to port 524, the service fails to properly handle the malformed data structure, leading to a system hang condition that effectively renders the directory service unavailable. This type of vulnerability falls under the category of improper input validation, which is commonly categorized as CWE-20 by the Common Weakness Enumeration system. The vulnerability's nature suggests that the service lacks proper error handling mechanisms to gracefully process malformed network requests, instead allowing the malformed input to cause the service thread or process to become unresponsive.
The operational impact of this vulnerability extends beyond simple service disruption, as Novell eDirectory serves as a foundational component for many enterprise network infrastructures. When the NCP service becomes unresponsive due to this flaw, it can result in widespread network access issues, as users and applications attempting to access directory services or network resources may encounter timeouts and connection failures. The vulnerability's remote exploitability means that attackers do not require local system access or authentication credentials to trigger the denial of service condition, making it particularly dangerous in networked environments where the service is exposed to untrusted networks. This weakness directly aligns with ATT&CK technique T1499.004, which involves network denial of service attacks targeting remote services.
Organizations affected by this vulnerability should immediately implement mitigations including applying the vendor-supplied patches for eDirectory versions 8.8.5.6 and 8.8.6.2, which contain the necessary fixes for the input validation issues. Network segmentation strategies should be employed to restrict access to port 524, limiting exposure to only trusted network segments and administrative systems. Additionally, implementing network monitoring and intrusion detection systems can help identify and alert on malformed FileSetLock requests that may indicate exploitation attempts. The vulnerability demonstrates the importance of robust input validation and proper error handling in network services, particularly those handling untrusted data from remote sources, as highlighted in industry best practices for secure software development and the principles outlined in the OWASP Top Ten security risks.