CVE-2018-10772 in Exiv2
Summary
by MITRE
The tEXtToDataBuf function in pngimage.cpp in Exiv2 through 0.26 allows remote attackers to cause a denial of service (application crash) or possibly have unspecified other impact via a crafted file.
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Analysis
by VulDB Data Team • 03/08/2023
The vulnerability identified as CVE-2018-10772 resides within the Exiv2 library's pngimage.cpp file, specifically within the tEXtToDataBuf function that processes png image files. This flaw represents a critical security issue affecting Exiv2 versions through 0.26, where maliciously crafted png files can trigger unpredictable behavior in applications that utilize this library for image processing. The vulnerability manifests as a potential denial of service condition that can cause application crashes, while also presenting possibilities for more severe consequences including arbitrary code execution or data corruption.
The technical root cause of this vulnerability stems from inadequate input validation and memory handling within the tEXtToDataBuf function. When processing specially crafted png files containing malformed tEXt chunks, the function fails to properly validate the data buffer boundaries and length parameters. This absence of proper boundary checking creates a condition where an attacker can manipulate the data structure to cause memory corruption, leading to application instability. The flaw aligns with CWE-121, which describes heap-based buffer overflow conditions, and CWE-125, which covers out-of-bounds read vulnerabilities. These weaknesses in memory management and input validation create pathways for attackers to exploit the library's processing functions.
From an operational perspective, this vulnerability poses significant risks to systems that rely on Exiv2 for image metadata handling and processing. Applications including photo management tools, web servers processing user-uploaded images, content management systems, and digital asset management platforms are all potential targets. The impact extends beyond simple service disruption as the vulnerability could enable attackers to execute arbitrary code on affected systems, particularly when the vulnerable library is used in web applications or server-side processing environments. This represents a serious concern for organizations maintaining image processing pipelines, as a single malicious file could compromise entire systems or applications that depend on Exiv2 functionality.
The exploitation of CVE-2018-10772 follows patterns consistent with attack frameworks such as those described in the MITRE ATT&CK matrix under the T1059.007 technique for command and script interpreter execution. Attackers can leverage this vulnerability by crafting malicious png files designed to trigger the buffer overflow condition during normal image processing operations. The vulnerability is particularly concerning in environments where users can upload files, as it enables a classic file upload attack vector that can be used to compromise web applications. Security professionals should consider this vulnerability when evaluating their threat landscape and implementing defensive measures.
Organizations should prioritize immediate remediation by upgrading to Exiv2 version 0.27 or later, where this vulnerability has been addressed through improved input validation and memory handling. Additionally, implementing proper file validation and sanitization measures can provide defense-in-depth protection against exploitation attempts. Network-based intrusion detection systems should be configured to monitor for suspicious file upload patterns and malformed png file signatures. Regular security assessments of systems using Exiv2 should include vulnerability scanning for this specific flaw, as well as broader security audits to identify potential attack surfaces that could be leveraged by adversaries exploiting similar memory corruption vulnerabilities.