CVE-2022-28237 in Acrobat Reader
Summary
by MITRE • 05/11/2022
Acrobat Reader DC versions 22.001.20085 (and earlier), 20.005.3031x (and earlier) and 17.012.30205 (and earlier) are affected by a use-after-free vulnerability in the processing of annotations that could result in arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.
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Analysis
by VulDB Data Team • 05/14/2022
This vulnerability exists in Adobe Acrobat Reader DC across multiple version ranges including 22.001.20085 and earlier, 20.005.3031x and earlier, and 17.012.30205 and earlier. The flaw manifests as a use-after-free condition during the processing of annotations within PDF documents. A use-after-free vulnerability occurs when a program continues to reference memory after it has been freed, creating a potential exploitation vector where attackers can manipulate memory contents to execute arbitrary code. This type of vulnerability is classified under CWE-416 as the use of freed memory, which represents a critical class of memory safety issues that can lead to remote code execution when properly exploited.
The technical exploitation requires user interaction through opening a maliciously crafted PDF file containing specially constructed annotations. When the vulnerable application processes these annotations, the memory management error occurs during the handling of annotation objects, potentially allowing attackers to overwrite memory locations with malicious payloads. The vulnerability operates at the application level within the PDF rendering engine, specifically targeting the annotation processing subsystem that handles various types of annotations such as text notes, highlights, and other interactive elements. This exploitation scenario aligns with ATT&CK technique T1203 which describes the use of malicious documents to execute code through applications that process rich text formats.
The operational impact of this vulnerability is significant as it enables remote code execution with the privileges of the current user, bypassing many traditional security controls that depend on user interaction being required for malicious code execution. An attacker could craft a PDF document containing malicious annotations that, when opened by an unsuspecting user, would trigger the use-after-free condition and potentially deliver a payload such as a remote access trojan or other malware. The vulnerability affects a wide range of Acrobat Reader versions, making it particularly dangerous as organizations often maintain multiple version deployments across their user base. This widespread impact increases the potential attack surface and makes the vulnerability attractive to threat actors seeking to maximize their exploitation effectiveness.
Organizations should prioritize immediate patching of affected Acrobat Reader installations to remediate this vulnerability. Adobe has released security updates for the affected versions, and administrators should ensure all users are running patched versions of the software. Additional mitigations include implementing application whitelisting controls to restrict execution of untrusted PDF files, configuring email filters to block suspicious PDF attachments, and educating users about the dangers of opening untrusted PDF documents. Network-based defenses such as web application firewalls and sandboxing solutions can provide additional layers of protection, though these measures are not substitutes for proper patch management. The vulnerability demonstrates the ongoing challenges in securing document processing applications where complex rendering engines can contain numerous potential attack vectors, emphasizing the need for continuous security monitoring and timely patch deployment across all software components that handle untrusted content.