CVE-2021-21073 in Animate
Summary
by MITRE • 03/13/2021
Adobe Animate version 21.0.3 (and earlier) is affected by an Out-of-bounds Read vulnerability. An unauthenticated attacker could leverage this vulnerability to disclose sensitive information 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 • 05/04/2025
Adobe Animate version 21.0.3 and earlier contains a critical out-of-bounds read vulnerability that falls under CWE-129, specifically categorized as an improper input validation flaw. This vulnerability stems from insufficient bounds checking within the application's handling of malformed file structures, particularly affecting the way the software processes certain animation file formats. The flaw allows an attacker to craft malicious files that, when opened by an unsuspecting user, can trigger memory access violations that expose sensitive data from adjacent memory locations. This type of vulnerability represents a classic information disclosure weakness where the application fails to validate the boundaries of data structures before accessing them, potentially revealing confidential information such as memory addresses, encryption keys, or other sensitive data that may be stored in adjacent memory regions.
The exploitation of this vulnerability requires social engineering to convince a victim to open a maliciously crafted file, making it a user-interaction dependent attack vector. This characteristic aligns with ATT&CK technique T1204.002 where adversaries use malicious documents to execute code or gain information. The attack surface is limited to users who actually open the crafted files, but the impact can be significant as the disclosed information may include system memory contents that could be leveraged for further exploitation or used to bypass security mechanisms. The vulnerability exists in the file parsing logic where Adobe Animate does not properly validate the size or structure of incoming animation data before attempting to read from memory locations that may extend beyond the allocated buffer boundaries.
The operational impact of this vulnerability extends beyond simple information disclosure, as the sensitive data exposure could potentially enable more sophisticated attacks such as privilege escalation or data exfiltration. Attackers who successfully exploit this vulnerability could gain insights into the application's memory layout, which might aid in developing more advanced exploits against the same or related software components. The out-of-bounds read could also potentially lead to application instability or crashes, creating a denial of service scenario that disrupts legitimate user operations. Organizations using Adobe Animate for animation development and publishing should be particularly concerned as this vulnerability could be exploited to access sensitive project data or development artifacts that may contain intellectual property or confidential information.
Mitigation strategies for this vulnerability should focus on immediate patching of Adobe Animate to version 21.0.4 or later, which contains the necessary fixes for the bounds checking issue. System administrators should implement strict file validation policies and consider sandboxing environments for opening potentially malicious files. Network-level controls such as email filtering and web proxies can help prevent users from accessing malicious files through common attack vectors. Additionally, security awareness training for users can reduce the success rate of social engineering attacks that rely on user interaction. The vulnerability demonstrates the importance of proper input validation and bounds checking in preventing information disclosure attacks, and organizations should review their software supply chain processes to ensure timely patch management. Regular security assessments of creative software applications should include thorough analysis of file parsing components, as these often represent high-value targets for attackers seeking to exploit memory corruption vulnerabilities.