CVE-2016-5080 in Communications Performance Intelligence Center (PIC) Software
Summary
by MITRE
Integer overflow in the rtxMemHeapAlloc function in asn1rt_a.lib in Objective Systems ASN1C for C/C++ before 7.0.2 allows context-dependent attackers to execute arbitrary code or cause a denial of service (heap-based buffer overflow), on a system running an application compiled by ASN1C, via crafted ASN.1 data.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 01/13/2025
The vulnerability identified as CVE-2016-5080 represents a critical integer overflow flaw within the Objective Systems ASN1C compiler suite, specifically affecting the rtxMemHeapAlloc function in the asn1rt_a.lib library. This issue impacts versions prior to 7.0.2 and exposes systems that compile applications using the ASN1C compiler to potential exploitation through maliciously crafted ASN.1 data structures. The flaw resides in the memory allocation handling mechanism of the ASN.1 runtime library, which is fundamental to applications that process ASN.1 encoded data. The vulnerability manifests when the system processes ASN.1 data that triggers an integer overflow condition during memory allocation calculations, potentially leading to heap corruption and subsequent arbitrary code execution or system instability.
The technical root cause of this vulnerability stems from inadequate input validation and integer overflow protection within the memory allocation routine. When the rtxMemHeapAlloc function processes memory requests derived from ASN.1 data structures, it fails to properly validate the size parameters that determine heap allocation amounts. This oversight creates a scenario where an attacker can craft ASN.1 data containing oversized or malformed size fields that, when processed, cause integer overflow arithmetic to produce unexpectedly small values. The resulting memory allocation becomes insufficient to accommodate the actual data being processed, creating heap-based buffer overflow conditions that can be exploited to overwrite adjacent memory regions. This class of vulnerability maps directly to CWE-190, which specifically addresses integer overflow and wraparound issues, and aligns with ATT&CK technique T1059.007 for execution through command and scripting interpreter.
The operational impact of this vulnerability extends across numerous systems and applications that rely on ASN.1 encoding for data interchange, particularly in telecommunications, network protocols, and security systems where ASN.1 is commonly employed. Applications compiled with vulnerable versions of the ASN1C compiler become susceptible to remote code execution when processing untrusted ASN.1 data streams, including network protocols, file formats, or data exchange mechanisms that utilize ASN.1 encoding. The vulnerability's context-dependent nature means that exploitation requires an attacker to have the ability to inject or influence ASN.1 data processed by the vulnerable application, making it particularly dangerous in environments where applications process data from external sources or untrusted networks. This could affect critical infrastructure systems, network equipment, security appliances, and any software components that implement ASN.1 data processing capabilities.
Mitigation strategies for CVE-2016-5080 primarily focus on immediate version upgrades to ASN1C 7.0.2 or later, which contain fixed implementations of the memory allocation functions. Organizations should conduct comprehensive inventory assessments to identify all systems and applications that utilize vulnerable versions of the ASN1C compiler and ensure complete remediation across their infrastructure. Additionally, implementing defensive programming practices such as input validation and bounds checking within applications that process ASN.1 data can provide additional protection layers. Network segmentation and access controls should be enforced to limit exposure of vulnerable applications to untrusted data sources, while monitoring systems should be configured to detect unusual patterns in ASN.1 data processing that might indicate exploitation attempts. The fix addresses the underlying integer overflow by implementing proper bounds checking and size validation mechanisms within the memory allocation routines, ensuring that allocation requests are properly validated before memory is allocated, thereby preventing the heap corruption that enables arbitrary code execution.