CVE-2025-64787 is a vulnerability identified in Adobe Acrobat Reader versions 24.001.30264, 20.005.30793, 25.001.20982, 24.001.30273, 20.005.30803, and earlier. The issue stems from improper verification of cryptographic signatures, classified under CWE-347, which leads to a security feature bypass. Specifically, the vulnerability allows an attacker to circumvent cryptographic protections that are intended to ensure the integrity and authenticity of data or documents within Acrobat Reader. By exploiting this flaw, an attacker can gain limited unauthorized write access to the system or files, potentially altering content or injecting malicious data. The attack vector requires local access (AV:L) but does not require privileges (PR:N) or user interaction (UI:R), meaning the attacker must have some level of access to the machine but does not need to trick the user into action. The vulnerability does not impact confidentiality or availability but affects integrity, resulting in a CVSS v3.1 base score of 3.3, categorized as low severity. No public exploits or active exploitation in the wild have been reported to date. The vulnerability's presence in widely used Acrobat Reader versions makes it relevant for organizations relying on this software for document handling and digital signatures. The lack of a patch link suggests that Adobe may not have released a fix at the time of this report, emphasizing the need for vigilance and interim mitigations.

For European organizations, the primary impact of CVE-2025-64787 lies in the potential compromise of document integrity and trustworthiness. Acrobat Reader is extensively used across Europe for viewing, signing, and managing PDF documents, including sensitive contracts, legal documents, and regulatory filings. An attacker exploiting this vulnerability could alter documents or bypass cryptographic signature verifications, undermining trust in digital signatures and potentially enabling fraud or data tampering. Although the vulnerability requires local access, insider threats or malware with local execution capabilities could leverage this flaw to escalate their impact. The limited unauthorized write access could facilitate further attacks or persistence mechanisms. The low CVSS score reflects limited scope and impact, but organizations in regulated sectors such as finance, legal, and government should consider the risk carefully. Failure to address this vulnerability could lead to compliance issues with European data integrity and cybersecurity regulations, including GDPR mandates on data protection and integrity.

1. Monitor Adobe’s official security advisories closely and apply patches immediately once they become available to address CVE-2025-64787. 2. Until patches are released, restrict local access to systems running vulnerable Acrobat Reader versions by enforcing strict access controls and endpoint security policies. 3. Employ application whitelisting and endpoint detection and response (EDR) solutions to detect and prevent unauthorized local modifications or suspicious activities related to Acrobat Reader processes. 4. Educate users about the risks of local malware and insider threats that could exploit this vulnerability, emphasizing the importance of maintaining secure endpoints. 5. Consider deploying alternative PDF readers with robust cryptographic verification if immediate patching is not feasible. 6. Implement integrity monitoring for critical documents and digital signatures to detect unauthorized changes promptly. 7. Regularly audit and review local user privileges to minimize the number of users with local access capable of exploiting this vulnerability.