CVE-2008-2696 in Exiv2
Summary
by MITRE
Exiv2 0.16 allows user-assisted remote attackers to cause a denial of service (divide-by-zero and application crash) via a zero value in Nikon lens information in the metadata of an image, related to "pretty printing" and the RationalValue::toLong function.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 08/20/2019
The vulnerability identified as CVE-2008-2696 affects Exiv2 version 0.16, a widely used library for reading and writing image metadata. This issue represents a classic divide-by-zero error that can be triggered through malformed metadata within image files, specifically targeting the Nikon lens information section. The flaw occurs when the library processes image files containing malformed metadata that includes a zero value in the lens information fields. This particular vulnerability demonstrates how metadata processing can introduce critical stability risks in image handling applications that rely on Exiv2 for their functionality.
The technical root cause of this vulnerability lies within the RationalValue::toLong function, which is responsible for converting rational numbers to long integers during the "pretty printing" process of metadata display. When the Nikon lens information contains a zero value in its denominator, the division operation within this function results in a divide-by-zero exception. This mathematical error causes the application to crash immediately, leading to a denial of service condition that affects any software utilizing Exiv2 for image metadata processing. The vulnerability is classified as a user-assisted remote attack because an attacker can craft malicious image files that trigger this condition when processed by vulnerable applications.
The operational impact of CVE-2008-2696 extends beyond simple application crashes, as it can be exploited in various real-world scenarios where image metadata processing is involved. Web applications, content management systems, and digital asset management platforms that use Exiv2 for automatic metadata extraction and display are all at risk. The vulnerability can be particularly dangerous in environments where automated image processing is performed, as a single malicious image file could cause cascading failures across multiple systems. This type of denial of service attack can be used to disrupt services, consume system resources through repeated crash cycles, or potentially provide a vector for more sophisticated attacks if combined with other vulnerabilities.
From a cybersecurity perspective, this vulnerability aligns with CWE-369, which addresses the divide-by-zero error condition, and demonstrates how metadata parsing can introduce stability risks in multimedia processing applications. The ATT&CK framework categorizes this as a denial of service attack vector through application-level vulnerabilities. Organizations should prioritize updating to Exiv2 versions that contain fixes for this issue, as the vulnerability affects the core functionality of metadata processing and can be exploited remotely without requiring special privileges. System administrators should also implement proper input validation and sanitization measures when processing user-uploaded images to mitigate potential exploitation of this and similar vulnerabilities in other components of their image processing pipelines.