CVE-2021-43021 is a memory corruption vulnerability classified under CWE-788 (Access of Memory Location After End of Buffer) affecting Adobe Premiere Rush version 1.5.16 and earlier. The vulnerability arises from insecure handling of a specially crafted EXR (OpenEXR image file format) file. When a user opens or processes a malicious EXR file within the affected versions of Adobe Premiere Rush, the application may access memory beyond the allocated buffer boundaries. This out-of-bounds memory access can lead to memory corruption, which attackers can leverage to execute arbitrary code with the privileges of the current user. Exploitation requires user interaction, specifically opening or importing a malicious EXR file into the application. There are no known public exploits in the wild as of the publication date, and no official patches or updates have been linked in the provided information. The vulnerability is medium severity, reflecting the balance between the potential impact and the requirement for user interaction.

For European organizations, the impact of this vulnerability depends largely on the usage of Adobe Premiere Rush within their environments. Adobe Premiere Rush is a video editing tool commonly used by creative professionals, marketing teams, and media companies. Successful exploitation could allow attackers to execute arbitrary code, potentially leading to unauthorized access, data theft, or lateral movement within a compromised system. Since the execution context is limited to the current user, the impact on system-wide integrity or availability may be limited unless the compromised user has elevated privileges. However, in environments where Premiere Rush is used on shared workstations or by users with administrative rights, the risk escalates. Additionally, compromised systems could serve as footholds for further attacks targeting intellectual property or sensitive multimedia content. The requirement for user interaction reduces the likelihood of widespread automated exploitation but does not eliminate targeted attacks, especially spear-phishing campaigns delivering malicious EXR files. Given the absence of known exploits, the immediate threat level is moderate, but organizations should remain vigilant.

1. Immediate mitigation involves restricting the use of Adobe Premiere Rush to trusted users and environments until an official patch is released. 2. Implement strict file validation and scanning policies for all incoming media files, especially EXR files, using advanced antivirus and endpoint detection and response (EDR) solutions capable of detecting malformed or malicious media content. 3. Educate users on the risks of opening unsolicited or suspicious media files, emphasizing the need to verify the source before importing files into Premiere Rush. 4. Employ application whitelisting and sandboxing techniques to limit the ability of compromised applications to execute arbitrary code or affect other system components. 5. Monitor systems for unusual behavior indicative of exploitation attempts, such as unexpected process launches or memory anomalies related to Adobe Premiere Rush. 6. Maintain up-to-date backups of critical data to enable recovery in case of compromise. 7. Once Adobe releases a patch, prioritize its deployment across all affected systems. 8. Consider network segmentation to isolate workstations running Premiere Rush from sensitive network segments to reduce lateral movement opportunities.