CVE-2018-15993 in Acrobat Reader
Summary
by MITRE
Adobe Acrobat and Reader versions 2019.008.20081 and earlier, 2019.008.20080 and earlier, 2019.008.20081 and earlier, 2017.011.30106 and earlier version, 2017.011.30105 and earlier version, 2015.006.30457 and earlier, and 2015.006.30456 and earlier have an use after free vulnerability. Successful exploitation could lead to arbitrary code execution.
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Analysis
by VulDB Data Team • 08/03/2024
The vulnerability identified as CVE-2018-15993 represents a critical use after free flaw affecting multiple versions of Adobe Acrobat and Reader software. This vulnerability falls under the CWE-416 category, which specifically addresses the use of freed memory conditions that can occur when a program continues to reference memory that has already been deallocated. The affected versions span across several major releases including 2019.008.20081 and earlier, 2017.011.30106 and earlier, and 2015.006.30457 and earlier, indicating a widespread issue that has persisted across multiple software iterations. The vulnerability manifests when the application processes maliciously crafted PDF files that trigger improper memory management during object handling, creating conditions where freed memory blocks can be accessed and manipulated by attackers.
The technical exploitation of this use after free vulnerability enables attackers to achieve arbitrary code execution on the target system. When a vulnerable application processes a specially crafted PDF document, the memory management routines fail to properly track object references, allowing an attacker to manipulate freed memory locations and potentially overwrite critical program structures or inject malicious code. This type of vulnerability is particularly dangerous because it can be triggered through simple document opening actions, making it an attractive target for phishing campaigns and social engineering attacks. The vulnerability's exploitation typically involves crafting a PDF file that causes the application to free memory associated with a specific object while still maintaining references to that memory location, subsequently allowing an attacker to control the execution flow of the application.
The operational impact of this vulnerability extends beyond simple privilege escalation or denial of service scenarios. Successful exploitation can result in complete system compromise, allowing attackers to execute arbitrary commands with the privileges of the affected user. This represents a significant threat in enterprise environments where Adobe Acrobat and Reader are widely deployed for document processing and viewing. The vulnerability's presence in multiple versions of the software means that organizations with legacy systems or delayed patch management processes remain at risk, creating persistent attack vectors that can be leveraged for data exfiltration, lateral movement, or establishment of persistent backdoors within network environments. The nature of PDF processing makes this vulnerability particularly dangerous as PDF files are commonly shared through email attachments, web downloads, and document sharing platforms.
Organizations should implement immediate mitigations including prompt patching of affected software versions, deployment of network segmentation strategies to limit PDF processing capabilities, and implementation of email filtering solutions that can detect and quarantine potentially malicious PDF attachments. Security teams should also consider deploying application whitelisting policies that restrict execution of Adobe Reader and Acrobat applications to trusted environments only. The ATT&CK framework categorizes this vulnerability under the T1059.007 technique for Windows Command Shell and T1203 for Exploitation for Client Execution, highlighting the potential for command execution and privilege escalation through this flaw. Additionally, organizations should conduct regular vulnerability assessments and penetration testing to identify any remaining instances of vulnerable software within their environment, as the use after free vulnerability can be particularly challenging to detect through automated scanning tools due to its reliance on specific memory access patterns that may not be immediately apparent during routine security assessments.