CVE-2011-3977 in NX Node
Summary
by MITRE
Unspecified vulnerability in nxconfigure.sh in NoMachine NX Node 3.x before 3.5.0-4 and NX Server 3.x before 3.5.0-5 allows local users to read arbitrary files via unknown vectors.
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Analysis
by VulDB Data Team • 11/23/2021
The vulnerability identified as CVE-2011-3977 represents a critical security flaw in the NoMachine NX remote desktop solution that affects both NX Node and NX Server components. This issue resides within the nxconfigure.sh script which is responsible for configuring the NX environment and establishing secure connections between client and server systems. The vulnerability manifests as an unspecified weakness that enables local users to access files they should not normally have permission to read, creating a significant privilege escalation risk within the NX infrastructure.
The technical nature of this flaw stems from inadequate input validation and access control mechanisms within the nxconfigure.sh script. Local users can exploit this vulnerability through unknown vectors that likely involve manipulation of file paths or configuration parameters that are processed by the script without proper sanitization. This allows unauthorized file access that could potentially expose sensitive system information, configuration files, or credentials stored within the NX environment. The vulnerability's classification as a local privilege escalation issue indicates that attackers must already have access to the system but can leverage this flaw to gain elevated privileges or access to restricted resources.
From an operational impact perspective, this vulnerability poses substantial risks to organizations relying on NoMachine NX for remote desktop services. The ability to read arbitrary files could lead to information disclosure attacks where attackers might extract sensitive data such as user credentials, system configurations, or application-specific information. The vulnerability affects versions prior to 3.5.0-4 for NX Node and 3.5.0-5 for NX Server, indicating that organizations running these older versions remain at risk. This issue directly violates the principle of least privilege and could enable attackers to gather intelligence for further exploitation or to compromise other system components.
Security professionals should note that this vulnerability aligns with CWE-22 (Improper Limitation of a Pathname to a Restricted Directory) and CWE-73 (External Control of File Name or Path) categories, which highlight the importance of proper input validation and path sanitization in preventing unauthorized file access. The attack surface extends beyond simple file reading to potential privilege escalation scenarios that could allow attackers to execute arbitrary commands or access additional system resources. Organizations should consider this vulnerability in their threat modeling exercises and ensure proper patch management protocols are in place to address such issues promptly.
The recommended mitigation strategy involves immediate deployment of patches released by NoMachine to update NX Node and NX Server installations to versions 3.5.0-4 and 3.5.0-5 respectively. Additionally, system administrators should review and tighten access controls on the nxconfigure.sh script and related configuration files to minimize potential attack vectors. Network segmentation and monitoring should be implemented to detect unauthorized access attempts or suspicious file access patterns. The vulnerability also underscores the importance of regular security assessments and vulnerability scanning to identify similar issues in other components of the NX infrastructure. Organizations should maintain updated security baselines and ensure that all remote desktop solutions are kept current with the latest security patches to prevent exploitation of known vulnerabilities.