CVE-2021-31503 in Brava Desktop
Summary
by MITRE • 08/03/2021
This vulnerability allows remote attackers to execute arbitrary code on affected installations of OpenText Brava! Desktop Build 16.6.3.84 (package 16.6.3.134). User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The specific flaw exists within the parsing of IGS files. The issue results from the lack of proper initialization of a pointer prior to accessing it. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-12690.
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Analysis
by VulDB Data Team • 08/07/2021
The vulnerability identified as CVE-2021-31503 represents a critical security flaw in OpenText Brava! Desktop version 16.6.3.84, specifically within the handling of IGS (Initial Graphics Exchange Specification) files. This remote code execution vulnerability stems from improper pointer initialization during file parsing operations, creating a dangerous condition where memory access occurs without proper validation. The flaw exists within the desktop application's file processing pipeline, where IGS files are parsed to extract graphical data for display purposes. The vulnerability is particularly concerning because it requires only user interaction to exploit, making it susceptible to social engineering attacks through malicious web pages or compromised files that users might encounter during normal operations.
The technical root cause of this vulnerability aligns with CWE-476, which describes NULL pointer dereference conditions that can lead to arbitrary code execution. When the application attempts to parse an IGS file, it fails to properly initialize a pointer variable before attempting to access memory locations referenced by that pointer. This initialization failure creates a scenario where the pointer contains unpredictable data, leading to memory access violations that can be manipulated by attackers. The lack of proper input validation and memory management in the IGS file parser creates an exploitable condition where crafted malicious input can cause the application to execute unintended code within the context of the current process. The vulnerability is particularly dangerous because it operates at the application level, potentially allowing attackers to gain full control of the user's system with the privileges of the running application.
The operational impact of this vulnerability extends beyond simple code execution, as it provides attackers with a complete compromise vector for targeted systems. The fact that exploitation requires only user interaction through visiting malicious pages or opening malicious files makes this vulnerability particularly dangerous in enterprise environments where users may encounter compromised content through email attachments, web downloads, or shared network resources. Attackers can leverage this vulnerability to install backdoors, steal sensitive data, or establish persistent access to compromised systems. The vulnerability affects the specific build version 16.6.3.84 of OpenText Brava! Desktop, which means organizations running this version are at risk, and the issue is categorized under the ATT&CK framework as a remote code execution technique that can be used for initial access and privilege escalation. The vulnerability's classification as ZDI-CAN-12690 indicates it was recognized by the Zero Day Initiative, highlighting its significance in the cybersecurity community.
Organizations affected by this vulnerability should immediately implement mitigations including updating to the latest version of OpenText Brava! Desktop where the vulnerability has been patched, implementing network segmentation to limit exposure, and deploying application whitelisting policies to restrict execution of unauthorized software. The patching process should be prioritized as this vulnerability enables complete system compromise, and administrators should also consider monitoring for suspicious file access patterns and implementing user education programs to reduce the risk of social engineering attacks. Additionally, security teams should review their incident response procedures to ensure rapid detection and containment of potential exploitation attempts, as the vulnerability's remote nature means attackers can potentially compromise systems from external networks without requiring physical access. Organizations should also consider implementing network-based intrusion detection systems to monitor for exploitation attempts targeting this specific vulnerability.