CVE-2021-21051 is a buffer overflow vulnerability (CWE-120) affecting Adobe Photoshop versions 21.2.4 and earlier, as well as 22.1.1 and earlier. The vulnerability arises when Photoshop parses a specially crafted JavaScript file embedded or loaded within the application. Due to improper bounds checking during this parsing process, an attacker can craft a malicious JavaScript file that triggers a buffer overflow, allowing arbitrary code execution within the context of the current user. Exploitation requires no authentication but does require user interaction, specifically that the victim opens the malicious file in Photoshop. This means the attacker must convince or trick the user into opening a crafted file, for example via phishing or malicious downloads. Successful exploitation could lead to execution of arbitrary code, potentially allowing the attacker to install malware, steal data accessible to the user, or manipulate files. However, the attack scope is limited to the privileges of the user running Photoshop, and no privilege escalation is directly indicated. There are no known exploits in the wild reported at the time of this analysis, and no official patches or updates are linked in the provided data, though Adobe typically addresses such vulnerabilities in security updates. The vulnerability is categorized as medium severity due to the requirement for user interaction and the limited scope of impact to the current user context.

For European organizations, the impact of CVE-2021-21051 depends largely on the prevalence of Adobe Photoshop usage within their environment and the security awareness of end users. Organizations in creative industries, media, advertising, and design sectors are more likely to be affected due to frequent use of Photoshop. An attacker exploiting this vulnerability could execute arbitrary code, potentially leading to data theft, lateral movement within the network if combined with other vulnerabilities, or deployment of ransomware or other malware. Since the vulnerability requires user interaction, phishing campaigns or social engineering could be leveraged to deliver malicious files. The impact on confidentiality is moderate, as attackers could access user-level data; integrity could be compromised if files are altered; availability could be affected if malware disrupts operations. However, the lack of privilege escalation limits the potential damage to user-level access. Organizations with strong endpoint protection, user training, and file scanning may mitigate risk, but those lacking such controls could face significant operational and reputational damage if targeted.

1. Ensure all Adobe Photoshop installations are updated to the latest available version beyond 22.1.1, as Adobe regularly releases security patches addressing such vulnerabilities. 2. Implement strict email and file filtering to block or quarantine suspicious JavaScript files or other potentially malicious attachments before they reach end users. 3. Educate users, especially those in creative roles, about the risks of opening files from untrusted sources and recognizing phishing attempts. 4. Employ application whitelisting or sandboxing for Photoshop to limit the ability of malicious code to execute or affect other system components. 5. Use endpoint detection and response (EDR) solutions capable of detecting anomalous behavior associated with exploitation attempts, such as unexpected script execution or memory corruption indicators. 6. Regularly back up critical data and ensure backups are isolated from the main network to recover from potential malware infections resulting from exploitation. 7. Monitor network traffic for unusual outbound connections that may indicate command and control communication following exploitation. 8. Restrict user privileges where possible, so even if code execution occurs, the attacker’s capabilities remain limited.