CVE-2019-17006 in Network Security Services
Summary
by MITRE • 10/23/2020
In Network Security Services (NSS) before 3.46, several cryptographic primitives had missing length checks. In cases where the application calling the library did not perform a sanity check on the inputs it could result in a crash due to a buffer overflow.
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Analysis
by VulDB Data Team • 11/26/2020
The Network Security Services library represents a critical component in cryptographic operations across numerous security applications and operating systems, providing essential functions for secure communications through protocols such as ssl tls and certificate handling. This vulnerability affects versions prior to 3.46 and specifically targets the cryptographic primitives within the library that process various cryptographic operations. The flaw manifests when these primitives lack proper validation of input lengths, creating potential pathways for buffer overflow conditions that can lead to application instability and system compromise.
The technical nature of this vulnerability stems from insufficient boundary checking within the cryptographic primitive implementations. When applications utilizing NSS call these functions without performing their own input sanitization, the library itself becomes vulnerable to malformed input data that exceeds expected buffer boundaries. This absence of length validation creates a condition where attackers can craft specially constructed cryptographic parameters that trigger buffer overflow scenarios during processing. The vulnerability operates at the intersection of improper input validation and memory safety issues, where the lack of bounds checking allows arbitrary data to overwrite adjacent memory locations.
From an operational perspective, this vulnerability presents significant risks to systems relying on NSS for security operations, particularly those that do not implement comprehensive input validation at higher application layers. The crash resulting from buffer overflow conditions can lead to denial of service attacks against services that depend on NSS functionality, while in more sophisticated attack scenarios could potentially be exploited to execute arbitrary code. The impact extends beyond simple service disruption to potential compromise of the entire security infrastructure that relies on these cryptographic operations for maintaining secure communications and data protection.
The vulnerability aligns with CWE-129 and CWE-787 categories that address insufficient input length validation and buffer overflow conditions respectively, representing fundamental security flaws in memory management and input handling within cryptographic libraries. From an attack framework perspective, this vulnerability could be categorized under ATT&CK technique T1059 for command and control communication and T1499 for network denial of service, depending on the specific exploitation method employed. Organizations should prioritize patching affected systems to version 3.46 or later, while implementing additional monitoring for unusual application behavior that might indicate exploitation attempts.
Mitigation strategies should focus on immediate patch deployment across all systems utilizing NSS libraries, combined with enhanced input validation practices in applications that interface with cryptographic functions. System administrators should implement monitoring solutions to detect potential exploitation attempts through abnormal memory usage patterns or application crashes. Additionally, organizations should consider implementing network segmentation and access controls to limit potential attack vectors and reduce the impact of successful exploitation attempts. The vulnerability demonstrates the critical importance of robust input validation in cryptographic libraries and highlights the need for comprehensive security testing of core security components that handle sensitive data processing operations.