CVE-2019-8203 in Acrobat Reader
Summary
by MITRE
Adobe Acrobat and Reader versions , 2019.012.20040 and earlier, 2017.011.30148 and earlier, 2017.011.30148 and earlier, 2015.006.30503 and earlier, and 2015.006.30503 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 • 01/16/2024
The vulnerability identified as CVE-2019-8203 represents a critical use after free flaw in Adobe Acrobat and Reader software versions spanning multiple release lines including 2019.012.20040 and earlier, 2017.011.30148 and earlier, and 2015.006.30503 and earlier. This type of vulnerability occurs when a program continues to reference memory that has already been freed, creating a scenario where malicious actors can manipulate the program flow to execute arbitrary code. The flaw manifests within the handling of specific document objects or memory management operations within the Adobe Reader environment, making it particularly dangerous for users who frequently process PDF documents from untrusted sources.
The technical implementation of this use after free vulnerability stems from improper memory management practices within Adobe's PDF processing engine. When a PDF document is parsed and certain objects are processed, the application allocates memory for these objects and subsequently frees them upon completion of their use. However, in the affected versions, the application fails to properly invalidate references to these freed memory locations, allowing an attacker to overwrite the freed memory with malicious data. This memory corruption can then be leveraged to redirect program execution flow through controlled data manipulation, potentially leading to complete system compromise.
The operational impact of CVE-2019-8203 extends beyond simple code execution, as it provides attackers with a pathway to achieve persistent system access through exploitation techniques that align with the attack tactics described in the MITRE ATT&CK framework under the T1059.007 technique for command and scripting interpreter. The vulnerability is particularly concerning because it affects multiple versions of Adobe Reader, creating a broad attack surface across different organizational environments. Organizations utilizing older versions of Adobe software are at significant risk, as the vulnerability can be exploited through malicious PDF files delivered via email attachments, web downloads, or other attack vectors that leverage the PDF processing capabilities of the affected applications.
Security professionals should note that this vulnerability falls under the CWE-416 category of use after free conditions, which represents a well-documented and frequently exploited class of memory safety issues. The exploitation of such vulnerabilities typically requires careful crafting of malicious PDF content that triggers the specific memory management flaw, often involving complex manipulation of PDF object structures and their interdependencies. Organizations should prioritize immediate remediation through patch management, as Adobe has released updates addressing this vulnerability in their software releases. Additionally, implementing defensive measures such as PDF sandboxing, restricted user privileges, and network-based protections can help mitigate the risk associated with this and similar vulnerabilities in the broader Adobe ecosystem.