CVE-2019-7809 in Acrobat Reader
Summary
by MITRE
Adobe Acrobat and Reader versions 2019.010.20100 and earlier, 2019.010.20099 and earlier, 2017.011.30140 and earlier, 2017.011.30138 and earlier, 2015.006.30495 and earlier, and 2015.006.30493 and earlier have a use after free vulnerability. Successful exploitation could lead to arbitrary code execution.
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Analysis
by VulDB Data Team • 06/16/2024
Adobe Acrobat and Reader applications contain a critical use after free vulnerability that affects multiple versions across different release cycles. This vulnerability stems from improper memory management practices where the software continues to reference memory locations after they have been freed, creating opportunities for attackers to manipulate program execution flow. The flaw exists within the parsing mechanisms of PDF documents, specifically when handling certain objects or structures that trigger memory deallocation followed by subsequent access attempts. According to CWE-416, this represents a classic use after free condition that can be exploited through crafted malicious PDF files delivered via phishing campaigns or malicious websites. The vulnerability manifests when the application processes malformed PDF content that causes memory to be freed while references to that memory remain active, enabling attackers to overwrite freed memory with malicious code or redirect execution flow to arbitrary locations.
The operational impact of this vulnerability extends beyond simple code execution to encompass complete system compromise when exploited successfully. Attackers can leverage this use after free condition to execute arbitrary code with the privileges of the victim user, potentially leading to full system compromise, data exfiltration, or deployment of additional malware. The vulnerability affects both desktop and mobile versions of Adobe Acrobat and Reader, making it particularly dangerous in enterprise environments where these applications are widely deployed. The exploitation process typically involves crafting a malicious PDF document that, when opened by the vulnerable application, triggers the memory management error and subsequently executes attacker-controlled code. This vulnerability aligns with ATT&CK technique T1059.007 for command and scripting interpreter and T1068 for exploit for privilege escalation, as successful exploitation often results in elevated privileges and further system compromise.
Mitigation strategies for CVE-2019-7809 should prioritize immediate patching of affected versions with the latest security updates from Adobe. Organizations should implement strict PDF document filtering policies that prevent execution of potentially malicious content, particularly in high-risk environments such as financial institutions or government agencies. Network-based protections including web application firewalls and email security solutions should be configured to block suspicious PDF attachments and content. Security teams should also consider implementing sandboxing mechanisms for PDF processing and establishing robust monitoring for unusual process behavior or memory access patterns. The vulnerability demonstrates the importance of proper memory management practices in security-critical applications, as highlighted by CWE-416's classification of use after free conditions as a fundamental memory safety issue. Regular security assessments and penetration testing should include validation of memory management practices in commonly used applications, particularly those handling untrusted input data. Additionally, user education regarding the dangers of opening PDF attachments from unknown sources remains crucial in reducing exploitation success rates, as many attacks rely on social engineering to deliver malicious payloads to unsuspecting users.