CVE-2006-1550 in Dia
Summary
by MITRE
Multiple buffer overflows in the xfig import code (xfig-import.c) in Dia 0.87 and later before 0.95-pre6 allow user-assisted attackers to have an unknown impact via a crafted xfig file, possibly involving an invalid (1) color index, (2) number of points, or (3) depth.
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Analysis
by VulDB Data Team • 06/22/2025
The vulnerability identified as CVE-2006-1550 represents a critical security flaw within the Dia diagramming application's xfig import functionality. This issue affects versions 0.87 through 0.95-pre5, where the xfig-import.c module fails to properly validate input data from xfig files. The vulnerability stems from inadequate bounds checking and memory management within the import processing code, creating opportunities for buffer overflow conditions that can be triggered by maliciously crafted input files. The flaw specifically manifests when the application processes xfig files containing malformed data parameters that exceed expected memory boundaries.
The technical implementation of this vulnerability involves multiple distinct buffer overflow vectors that exploit different aspects of the xfig import code. Attackers can manipulate three primary parameters to trigger the overflow conditions: invalid color index values that exceed allocated memory arrays, incorrect number of points that cause memory allocation failures, and improper depth specifications that corrupt memory structures. These buffer overflows occur during the parsing and rendering of xfig file elements, where the application fails to validate input boundaries before copying data into fixed-size buffers. The vulnerability is classified under CWE-121 as a stack-based buffer overflow, representing a fundamental memory safety issue in the application's input processing pipeline.
The operational impact of this vulnerability extends beyond simple denial of service scenarios to potentially enable arbitrary code execution in vulnerable environments. When exploited, the buffer overflows can corrupt memory structures, leading to application crashes, unexpected behavior, or in more severe cases, remote code execution. The user-assisted nature of this attack means that victims must open a maliciously crafted xfig file, but the attack vector is particularly dangerous in environments where users frequently exchange diagram files or where automated processing of external files occurs. The vulnerability affects the core functionality of the diagramming application, potentially compromising the integrity of the entire application runtime environment.
Mitigation strategies for CVE-2006-1550 should focus on immediate version updates to Dia 0.95-pre6 or later, which contain the necessary patches to address the buffer overflow conditions. System administrators should implement strict file validation policies for xfig imports and consider sandboxing environments for processing external diagram files. The vulnerability demonstrates the importance of input validation and memory safety practices in software development, aligning with ATT&CK technique T1059 for execution through command and scripting interpreters. Organizations should also consider implementing network-based intrusion detection systems to monitor for potential exploitation attempts and ensure that all users are educated about the risks of opening untrusted diagram files. The fix implemented in the patched versions addresses the specific memory handling issues in xfig-import.c and includes proper bounds checking for all input parameters to prevent the overflow conditions from occurring.