CVE-2023-31979 in Catdoc
Summary
by MITRE • 05/09/2023
Catdoc v0.95 was discovered to contain a global buffer overflow via the function process_file at /src/reader.c.
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Analysis
by VulDB Data Team • 02/18/2026
The vulnerability identified as CVE-2023-31979 represents a critical buffer overflow flaw in catdoc version 0.95 that resides within the process_file function located in the /src/reader.c source file. This issue constitutes a classic global buffer overflow vulnerability that occurs when a program writes more data to a fixed-length buffer than it can accommodate, potentially leading to memory corruption and arbitrary code execution. The catdoc utility is commonly used for extracting text from Microsoft Office documents including .doc files, making this vulnerability particularly concerning for systems that process untrusted document content. The flaw exists in the document parsing logic where insufficient bounds checking occurs during file processing operations.
From a technical perspective, this buffer overflow manifests when the process_file function fails to properly validate input lengths before copying data into global buffers. The vulnerability falls under CWE-121, which specifically addresses stack-based buffer overflow conditions, though in this case the overflow occurs in global memory space rather than stack space. The implementation likely lacks proper input sanitization mechanisms that would normally validate the size of incoming document data against predetermined buffer limits. Attackers could exploit this by crafting maliciously formatted documents that, when processed by catdoc, trigger the overflow condition and potentially allow for remote code execution or system compromise.
The operational impact of CVE-2023-31979 extends beyond simple denial of service scenarios, as this vulnerability could enable attackers to execute arbitrary code with the privileges of the user running catdoc. Systems that automatically process or convert Microsoft Office documents, such as email servers, document management systems, or automated content processing pipelines, become particularly vulnerable to exploitation. The vulnerability's exploitation aligns with ATT&CK technique T1203, which involves the use of malicious documents to gain initial access or execute commands on target systems. Organizations using catdoc in production environments without proper input validation or sandboxing mechanisms face significant risk of unauthorized access and potential data breaches.
Mitigation strategies for this vulnerability should prioritize immediate patching of the catdoc utility to version 0.96 or later, which contains the necessary fixes for the buffer overflow condition. System administrators should implement input validation measures that limit document size and content type processing, while also employing sandboxing techniques to isolate document processing operations. Network segmentation and access controls should be enforced to limit exposure of systems running catdoc to untrusted inputs. Additionally, regular security assessments should verify that no other applications within the environment contain similar buffer overflow vulnerabilities, as this flaw represents a common class of security issues that often appear in legacy document processing libraries. The vulnerability demonstrates the importance of maintaining up-to-date software libraries and implementing robust input validation practices to prevent exploitation of memory corruption vulnerabilities.