CVE-2021-37530 in fig2dev
Summary
by MITRE • 01/13/2022
A denial of service vulnerabiity exists in fig2dev through 3.28a due to a segfault in the open_stream function in readpics.c.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 01/15/2022
The vulnerability CVE-2021-37530 represents a critical denial of service weakness in the fig2dev utility version 3.28a and earlier, specifically manifesting as a segmentation fault within the open_stream function located in the readpics.c source file. This issue arises during the processing of malformed or specially crafted input files that the fig2dev tool attempts to parse and convert, creating a scenario where legitimate system resources become unavailable to authorized users. The vulnerability stems from inadequate input validation and error handling mechanisms within the software's stream processing logic, which fails to properly manage memory access patterns when encountering unexpected data structures during file parsing operations.
The technical exploitation of this vulnerability occurs when an attacker provides malicious input to the fig2dev utility, causing the application to attempt accessing invalid memory addresses through the open_stream function. This function is responsible for opening and managing file streams during the reading of picture data, and the segmentation fault occurs when the program tries to dereference a pointer that points to an invalid memory location or when buffer overflow conditions are triggered during stream processing. The flaw aligns with CWE-125, which describes out-of-bounds read conditions, and CWE-119, which encompasses improper access to memory buffers, making this a particularly dangerous vulnerability for systems that process untrusted input through the fig2dev utility.
From an operational perspective, this vulnerability presents significant risks to systems that rely on fig2dev for converting figure files, particularly in environments where automated processing or user-provided input is common. The segmentation fault results in an application crash that can be exploited to deny service to legitimate users who depend on the utility for document conversion tasks. This denial of service can be particularly impactful in server environments or automated workflows where fig2dev is part of a larger processing pipeline, potentially causing cascading failures throughout dependent systems. The vulnerability also poses risks in web applications or services that might invoke fig2dev to process user-uploaded files, as attackers could systematically crash the service by submitting malicious input files.
The mitigation strategy for CVE-2021-37530 primarily involves upgrading to fig2dev version 3.28b or later, where the segmentation fault has been addressed through improved input validation and memory management practices. System administrators should also implement proper input sanitization measures when processing files through fig2dev, including validating file formats and implementing resource limits to prevent excessive memory consumption. Additionally, deploying intrusion detection systems that monitor for unusual patterns of file processing or application crashes can help detect potential exploitation attempts. Organizations should consider implementing sandboxing techniques or containerization for fig2dev usage to limit the impact of any potential exploitation attempts, and regular security assessments should be conducted to identify similar vulnerabilities in other utility functions that may process external input data. This vulnerability demonstrates the importance of robust error handling in utility applications and aligns with ATT&CK technique T1499.004, which covers network denial of service attacks through application-level resource exhaustion, emphasizing the need for comprehensive defensive measures against such threats in system security architectures.