CVE-2015-4444 in Acrobat Reader
Summary
by MITRE
Adobe Reader and Acrobat 10.x before 10.1.15 and 11.x before 11.0.12, Acrobat and Acrobat Reader DC Classic before 2015.006.30060, and Acrobat and Acrobat Reader DC Continuous before 2015.008.20082 on Windows and OS X allow attackers to cause a denial of service (NULL pointer dereference) via unspecified vectors, a different vulnerability than CVE-2015-4443.
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Analysis
by VulDB Data Team • 06/01/2022
Adobe Reader and Acrobat versions prior to specific patch releases contain a critical denial of service vulnerability that stems from improper handling of malformed input data during document processing. This vulnerability manifests as a NULL pointer dereference condition that occurs when the affected software attempts to access memory locations that have not been properly initialized or allocated. The flaw exists within the core document parsing and rendering components of the software, specifically in how it processes certain PDF file structures that contain invalid or unexpected data patterns. Attackers can exploit this weakness by crafting malicious PDF documents that trigger the NULL pointer dereference when the vulnerable application attempts to render or process the document content. The vulnerability affects multiple product lines including Adobe Reader 10.x versions before 10.1.15 and 11.x versions before 11.0.12, along with various Acrobat and Acrobat Reader DC Classic and Continuous versions released in 2015. The impact of this vulnerability extends across both Windows and macOS operating systems, making it particularly concerning given the widespread deployment of Adobe Reader across enterprise and consumer environments.
The technical nature of this vulnerability aligns with CWE-476 which specifically addresses NULL pointer dereference conditions in software applications. This weakness represents a fundamental programming error where the application fails to validate pointer values before attempting to dereference them, leading to application crashes or unexpected behavior. The vulnerability operates through unspecified vectors that likely involve manipulation of PDF object structures, cross-reference tables, or embedded content that causes the parsing engine to attempt operations on uninitialized memory addresses. When the software encounters these malformed data structures, it attempts to access memory locations that contain NULL values, resulting in a segmentation fault or system crash that terminates the application process. The fact that this vulnerability is separate from CVE-2015-4443 indicates it represents a distinct code path within the software's processing logic, suggesting that multiple pathways exist for similar types of input validation failures.
The operational impact of this vulnerability is significant for organizations that rely heavily on Adobe Reader for document processing and viewing. A successful exploitation of this denial of service condition can result in complete application termination, requiring users to manually restart the software and potentially lose unsaved work or context. In enterprise environments where Adobe Reader is extensively used for document sharing, processing, and collaboration, this vulnerability could be exploited to disrupt business operations through repeated application crashes. The vulnerability is particularly dangerous when considering that PDF files are commonly shared via email, file transfers, and web downloads, making it relatively easy for attackers to deliver malicious payloads to unsuspecting users. Network administrators and security teams must also consider that this vulnerability could be leveraged as part of broader attack campaigns where initial access is achieved through other means, and this denial of service capability is used to further compromise systems or disrupt operations. The vulnerability's presence in multiple product versions and operating systems increases its attack surface and makes comprehensive patch management essential for mitigating risk.
Organizations should prioritize immediate patch deployment for all affected Adobe Reader and Acrobat versions to remediate this vulnerability effectively. The recommended mitigation strategy involves updating to the latest available versions that contain the necessary code fixes for the NULL pointer dereference issue. Security teams should implement network monitoring to detect potential exploitation attempts through suspicious PDF file transfers or unusual application crash patterns. Additional defensive measures include implementing email filtering rules to block PDF attachments from untrusted sources, deploying sandboxing technologies for PDF processing, and conducting user awareness training to recognize potentially malicious document attachments. System administrators should also consider implementing application whitelisting policies that restrict execution of Adobe Reader to known good configurations while monitoring for unauthorized software installations. The vulnerability's classification as a denial of service issue means that organizations should also prepare incident response procedures to handle potential application crashes and ensure business continuity. Regular vulnerability scanning and penetration testing should be conducted to identify other potential weaknesses in the software stack and ensure that similar input validation flaws are not present in other applications or systems within the organization's infrastructure.