CVE-2021-42269 in Animate
Summary
by MITRE • 11/18/2021
Adobe Animate version 21.0.9 (and earlier) are affected by a use-after-free vulnerability in the processing of a malformed FLA file 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 • 11/22/2021
Adobe Animate version 21.0.9 and earlier contains a critical use-after-free vulnerability classified as CVE-2021-42269 that stems from improper memory management during the processing of malformed FLA files. This vulnerability resides in the application's file parsing logic where insufficient bounds checking and memory deallocation procedures create conditions where freed memory blocks can be accessed and reused by subsequent operations. The flaw manifests when the software attempts to process corrupted or maliciously crafted FLA files, which are Adobe's native animation project formats used for creating interactive content and animations. The use-after-free condition occurs because the application allocates memory for file structures and subsequently frees it without proper nullification, allowing attackers to manipulate the freed memory location and potentially execute arbitrary code with the privileges of the currently logged-in user.
The operational impact of this vulnerability extends beyond simple code execution as it represents a sophisticated attack vector that leverages social engineering principles to achieve privilege escalation. According to the ATT&CK framework, this vulnerability aligns with technique T1059.007 for command and scripting interpreter and T1548.001 for abuse of privileges, as successful exploitation allows attackers to execute malicious payloads with elevated user permissions. The vulnerability's exploitation requires user interaction, making it particularly dangerous in targeted attack scenarios where adversaries must convince victims to open malicious FLA files, often through phishing campaigns or compromised websites. The attack surface is limited to users who have Adobe Animate installed, but given the software's widespread use in creative industries and educational institutions, the potential impact is significant. This vulnerability demonstrates a classic memory corruption flaw that can be exploited through file format parsing, similar to other well-known use-after-free vulnerabilities found in Adobe Acrobat and other software products.
Mitigation strategies for CVE-2021-42269 should prioritize immediate software updates to Adobe Animate version 21.1.0 or later, which contain patches addressing the memory management issues in FLA file processing. Organizations should implement strict file validation policies, particularly for incoming FLA files from untrusted sources, and consider deploying sandboxing solutions to isolate file processing activities. The CWE database categorizes this vulnerability under CWE-416 as use-after-free, which indicates the need for robust memory management practices including proper deallocation and null pointer assignment. Network security controls such as email filtering and web proxy rules can help prevent users from accessing malicious FLA files through phishing campaigns, while endpoint detection and response solutions should monitor for suspicious file operations and process behavior that might indicate exploitation attempts. Security awareness training for users remains crucial as the requirement for user interaction makes social engineering a primary attack vector, emphasizing the importance of verifying file sources and avoiding opening suspicious attachments or downloading untrusted content.