CVE-2021-40752 in After Effects
Summary
by MITRE • 11/18/2021
Adobe After Effects version 18.4 (and earlier) is affected by a memory corruption vulnerability due to insecure handling of a malicious .m4a file, potentially resulting in arbitrary code execution in the context of the current user. User interaction is required in that the victim must open a specially crafted file to exploit this vulnerability.
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Analysis
by VulDB Data Team • 05/02/2025
Adobe After Effects version 18.4 and earlier versions contain a critical memory corruption vulnerability that stems from improper handling of maliciously crafted .m4a audio files. This vulnerability manifests as an insecure memory management flaw that occurs during the processing of media files, specifically when the application attempts to parse and decode the metadata or audio data within these files. The flaw represents a classic buffer overflow condition where insufficient bounds checking allows malicious input to overwrite adjacent memory locations, potentially leading to arbitrary code execution. The vulnerability is classified as a memory corruption issue that aligns with CWE-121, which describes unsafe use of memory allocation and deallocation operations. Attackers can exploit this weakness by crafting a specially formatted .m4a file that triggers the vulnerable code path when opened by the affected Adobe After Effects application.
The operational impact of this vulnerability extends beyond simple code execution, as it enables attackers to gain full control of the victim's system with the privileges of the currently logged-in user. This represents a significant escalation from a simple denial-of-service condition to a full system compromise, particularly in professional environments where After Effects is commonly used for video editing and post-production work. The requirement for user interaction makes this vulnerability more difficult to exploit at scale, but also means that targeted attacks against specific users or organizations remain highly effective. The attack vector requires social engineering to convince users to open the malicious file, making this a prime example of a user-initiated exploitation scenario that aligns with ATT&CK technique T1204.002, which covers "User Execution: Malicious File." The vulnerability affects the application's media processing pipeline, where it fails to properly validate the structure and content of incoming audio files before attempting to process them.
Mitigation strategies for this vulnerability focus on both immediate user protection and long-term system hardening measures. Users should immediately update to Adobe After Effects version 18.5 or later, which contains patches addressing this specific memory corruption flaw. Organizations should implement strict file validation policies and consider deploying sandboxing solutions for media processing activities to limit the potential impact of successful exploitation attempts. Security teams should monitor for indicators of compromise related to this vulnerability, including unusual file access patterns or attempts to execute malicious code within the After Effects environment. The patch released by Adobe addresses the root cause by implementing proper bounds checking and memory management practices during .m4a file processing, preventing the overflow condition that previously allowed attackers to manipulate memory contents. Additionally, administrators should consider implementing application whitelisting policies that restrict the execution of untrusted media files, particularly in environments where After Effects is used for creative work involving external file imports. The vulnerability demonstrates the importance of proper input validation in multimedia processing applications, as similar flaws could potentially exist in other components of the Adobe Creative Suite that handle external media files, making this a critical security consideration for any organization using Adobe's professional video editing tools.