CVE-2018-4989 in Acrobat Reader
Summary
by MITRE
Adobe Acrobat and Reader versions 2018.011.20038 and earlier, 2017.011.30079 and earlier, and 2015.006.30417 and earlier have a Use-after-free vulnerability. Successful exploitation could lead to arbitrary code execution in the context of the current user.
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Analysis
by VulDB Data Team • 07/21/2024
The vulnerability identified as CVE-2018-4989 represents a critical use-after-free flaw affecting multiple versions of Adobe Acrobat and Reader software. This vulnerability resides within the document processing components of these applications, specifically within the handling of PDF objects that are improperly managed during memory allocation and deallocation processes. The flaw manifests when the software attempts to access memory locations that have already been freed, creating a scenario where malicious code can potentially overwrite or manipulate the freed memory space to execute arbitrary instructions.
The technical nature of this vulnerability aligns with CWE-416, which classifies use-after-free conditions as a serious memory safety issue. When Adobe Acrobat or Reader processes certain PDF files containing maliciously crafted objects, the application's memory management routines fail to properly track object references, leading to situations where freed memory blocks are accessed or reused. This particular vulnerability affects versions from 2015 through 2018, spanning multiple release cycles and indicating a persistent flaw in the software's memory handling mechanisms. The exploitation requires a user to open a specially crafted malicious PDF file, which triggers the memory corruption during normal document processing operations.
The operational impact of this vulnerability extends beyond simple privilege escalation as it provides attackers with a path to achieve arbitrary code execution within the user context where the vulnerable application runs. This means that successful exploitation could allow an attacker to execute malicious code with the same permissions and privileges as the legitimate user, potentially leading to data theft, system compromise, or further lateral movement within a network environment. The vulnerability is particularly concerning because it requires no special privileges to exploit, as it leverages the normal user interaction patterns with PDF documents. The attack surface is broad since PDF files are commonly encountered in email attachments, web downloads, and shared documents across various industries.
Organizations should prioritize immediate remediation by updating to patched versions of Adobe Acrobat and Reader, as Adobe released security updates specifically addressing this vulnerability. System administrators should implement application whitelisting policies to restrict execution of untrusted PDF files and consider deploying sandboxing solutions to isolate PDF processing operations. The vulnerability also maps to several ATT&CK techniques including initial access through malicious files and execution through legitimate system processes. Network monitoring should be enhanced to detect suspicious PDF file transfers, and user education programs should emphasize the risks of opening unexpected PDF attachments. Additionally, implementing security controls such as email filtering and web proxy configurations can help prevent the delivery of malicious PDF files to end-user systems, reducing the overall attack surface and potential impact of this use-after-free vulnerability.