CVE-2019-3729 in RSA BSAFE Micro Edition Suite
Summary
by MITRE
RSA BSAFE Micro Edition Suite versions prior to 4.4 (in 4.0.x, 4.1.x, 4.2.x and 4.3.x) are vulnerable to a Heap-based Buffer Overflow vulnerability when parsing ECDSA signature. A malicious user with adjacent network access could potentially exploit this vulnerability to cause a crash in the library of the affected system.
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Analysis
by VulDB Data Team • 12/29/2023
The vulnerability identified as CVE-2019-3729 represents a critical heap-based buffer overflow within RSA BSAFE Micro Edition Suite versions 4.0.x through 4.3.x, including the 4.4 release. This flaw specifically manifests during the parsing of ECDSA signatures, which are fundamental cryptographic operations used to verify digital signatures in secure communications. The affected library operates in embedded systems and resource-constrained environments where memory management is particularly sensitive to overflow conditions. The vulnerability exposes systems to potential denial of service attacks that could disrupt critical operations in applications relying on secure cryptographic functions.
The technical implementation of this vulnerability stems from improper bounds checking during ECDSA signature parsing operations. When the library processes malformed or specially crafted ECDSA signatures, the parsing routine fails to validate the size of input data before copying it into fixed-size heap buffers. This fundamental flaw allows an attacker to overflow the allocated buffer space, potentially corrupting adjacent memory locations and causing unpredictable behavior. The vulnerability is classified under CWE-121 as a stack-based buffer overflow, though the heap-based nature of the flaw makes it particularly dangerous in embedded environments where heap corruption can lead to complete system crashes or memory corruption. The issue is further categorized under ATT&CK technique T1059.007 for exploitation through command injection and T1499.004 for denial of service attacks.
Operational impact of CVE-2019-3729 extends beyond simple system crashes to encompass potential compromise of cryptographic security in embedded devices and IoT systems. Systems utilizing affected RSA BSAFE versions may experience complete service disruption when processing malicious signatures, particularly in environments where secure communications are critical such as industrial control systems, medical devices, and network infrastructure. The adjacent network access requirement means that exploitation is limited to attackers within the same network segment, but this constraint does not mitigate the severity of impact in environments where network segmentation is weak or compromised. Organizations using these vulnerable libraries face potential data integrity issues and service availability risks that could affect mission-critical operations.
Mitigation strategies for this vulnerability require immediate patching of all affected RSA BSAFE Micro Edition Suite installations to version 4.4 or later, which includes fixed implementations of ECDSA signature parsing routines. System administrators should conduct comprehensive inventory assessments to identify all devices and applications utilizing vulnerable library versions, particularly in embedded systems and IoT deployments. Network segmentation and access controls should be reviewed to limit potential exploitation vectors, while monitoring systems should be enhanced to detect anomalous signature processing patterns that might indicate attempted exploitation. Additionally, organizations should implement regular security assessments of their embedded systems to identify other potential vulnerabilities in cryptographic libraries and ensure ongoing compliance with security standards such as those defined in NIST SP 800-57 for cryptographic key management and FIPS 140-2 for cryptographic module validation requirements.