CVE-2017-11209 in Acrobat Reader
Summary
by MITRE
Adobe Acrobat Reader 2017.009.20058 and earlier, 2017.008.30051 and earlier, 2015.006.30306 and earlier, and 11.0.20 and earlier has an exploitable memory corruption vulnerability that occurs when reading a JPEG file embedded within XML Paper Specification (XPS) file. Successful exploitation could lead to arbitrary code execution.
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Analysis
by VulDB Data Team • 01/08/2021
This vulnerability exists in Adobe Acrobat Reader versions up to and including 2017.009.20058, 2017.008.30051, 2015.006.30306, and 11.0.20, representing a critical memory corruption flaw that can be exploited through maliciously crafted XPS files containing embedded JPEG images. The vulnerability specifically manifests when the application processes JPEG data within XPS documents, creating a path for remote code execution attacks. The flaw stems from inadequate input validation and memory management during the parsing of embedded image data, allowing attackers to craft malicious XPS files that trigger buffer overflows or other memory corruption conditions. This vulnerability aligns with CWE-121, heap-based buffer overflow, and CWE-125, out-of-bounds read, making it particularly dangerous as it can be exploited without user interaction once a malicious document is opened. The exploitation technique leverages the XPS file format's ability to embed various image formats including JPEG, which Acrobat Reader processes using internal libraries that fail to properly validate the image data boundaries.
The operational impact of this vulnerability is severe as it enables attackers to execute arbitrary code on vulnerable systems with the privileges of the user running Acrobat Reader. This creates a significant attack surface since XPS files can be delivered through various vectors including email attachments, web downloads, or malicious websites. The vulnerability can be exploited in both targeted attacks against specific users and mass phishing campaigns, as XPS files are often perceived as legitimate documents due to their association with Microsoft's document format. Successful exploitation allows attackers to bypass traditional security controls, install malware, steal sensitive information, or establish persistent access to compromised systems. The attack chain typically involves crafting an XPS file with malicious JPEG data that, when opened by the vulnerable Acrobat Reader, triggers the memory corruption leading to code execution. This vulnerability also maps to ATT&CK technique T1204.002, legitimate program execution, as it leverages a legitimate application to execute malicious code.
Mitigation strategies should focus on immediate patching of all affected Adobe Acrobat Reader versions, as well as implementing strict file type controls and content filtering for XPS and XML files. Organizations should disable automatic opening of potentially dangerous file types and implement application whitelisting to prevent execution of untrusted XPS documents. Network-based protections such as deep packet inspection and sandboxing of suspicious documents can provide additional layers of defense. Security awareness training should emphasize the risks of opening unexpected documents, particularly those received via email or downloaded from untrusted sources. The vulnerability highlights the importance of keeping software updated, as Adobe released patches addressing this specific memory corruption issue in subsequent releases. System administrators should also consider implementing email filtering rules to block XPS files from unknown senders and monitor for unusual document opening patterns that might indicate exploitation attempts. Regular vulnerability assessments and penetration testing should include verification of Acrobat Reader installations to ensure all systems are properly patched against this and similar memory corruption vulnerabilities.