CVE-2019-8100 in Acrobat Reader
Summary
by MITRE
Adobe Acrobat and Reader versions, 2019.012.20035 and earlier, 2019.012.20035 and earlier, 2017.011.30142 and earlier, 2017.011.30143 and earlier, 2017.011.30142 and earlier, 2015.006.30497 and earlier, and 2015.006.30498 and earlier have an out-of-bounds write vulnerability. Successful exploitation could lead to arbitrary code execution.
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Analysis
by VulDB Data Team • 07/28/2020
Adobe Acrobat and Reader versions prior to specific patches contain a critical out-of-bounds write vulnerability that represents a significant security risk for enterprise environments. This vulnerability affects multiple product versions including 2019.012.20035, 2017.011.30142, 2017.011.30143, and 2015.006.30497, among others, where the software fails to properly validate input data before writing to memory locations. The flaw manifests when processing specially crafted pdf documents that contain malformed data structures, specifically within the document parsing routines that handle various pdf objects and streams. When an attacker successfully exploits this vulnerability, the out-of-bounds write operation can overwrite adjacent memory locations, potentially allowing for arbitrary code execution within the context of the vulnerable application.
The technical nature of this vulnerability aligns with CWE-787, which describes out-of-bounds write conditions where a program writes data past the end or beginning of a prepared array or buffer. This particular flaw falls under the broader category of memory corruption vulnerabilities that are highly prized by threat actors due to their potential for privilege escalation and remote code execution. The vulnerability's exploitability is enhanced by the fact that it can be triggered through simple pdf file manipulation, making it particularly dangerous in environments where users frequently open pdf documents from untrusted sources. Attackers can craft malicious pdf files that, when opened by an affected version of Adobe Reader or Acrobat, will cause the application to write data beyond allocated memory boundaries, potentially leading to complete system compromise.
The operational impact of this vulnerability extends beyond simple exploitation as it affects organizations that rely heavily on pdf document processing and viewing. Enterprise environments that have not updated to patched versions remain vulnerable to targeted attacks where adversaries could deliver malicious pdf files through email phishing campaigns, web downloads, or compromised websites. The vulnerability's presence in multiple versions including older releases like 2015.006.30497 indicates that organizations with legacy systems or those that delay patch deployment face prolonged exposure. Organizations may experience unauthorized access to sensitive data, system compromise, and potential lateral movement within their networks if attackers successfully exploit this vulnerability. The risk is particularly elevated for users who frequently open pdf documents from external sources or those who lack proper email filtering and endpoint protection measures.
Organizations should implement immediate mitigation strategies including prompt patch deployment for all affected Adobe Acrobat and Reader versions, preferably following the official Adobe security bulletins and update schedules. System administrators should consider implementing additional protective measures such as pdf sandboxing features, restricted file type handling, and enhanced email filtering to prevent delivery of malicious pdf files. Network segmentation and endpoint protection solutions should be configured to monitor for suspicious pdf file activity and unusual process behavior. Regular vulnerability scanning and patch management processes should be enhanced to ensure timely identification and remediation of similar vulnerabilities. The ATT&CK framework categorizes this type of vulnerability exploitation under T1059 Command and Control, specifically targeting T1059.007 Unix Shell and T1059.008 Windows Command Shell, as attackers may attempt to establish persistent access through compromised applications. Organizations should also conduct regular security awareness training to educate users about the risks of opening untrusted pdf files and the importance of maintaining updated software versions.