CVE-2025-64786 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 flaw stems from improper verification of cryptographic signatures (CWE-347), which means that Acrobat Reader does not correctly validate the authenticity of digital signatures on documents. This improper verification can allow an attacker to bypass security features designed to protect document integrity. Specifically, the attacker could gain limited unauthorized write access, potentially modifying documents or associated data in ways that should be prevented by the signature verification process. The vulnerability does not require user interaction to be exploited, increasing its risk profile slightly, but the attack vector is local (AV:L), meaning the attacker needs local access to the system. The CVSS score is 3.3 (low severity), reflecting limited impact primarily on integrity, no impact on confidentiality or availability, and no privileges required. No known exploits have been reported in the wild so far. The vulnerability is significant in environments where document authenticity and integrity are critical, such as legal, financial, and governmental sectors. Since Adobe Acrobat Reader is widely used across Europe, especially in enterprise and public sectors, this vulnerability warrants attention. However, the lack of remote exploitability and the low severity score indicate that the threat level is currently low. Organizations should monitor Adobe's security advisories for patches and apply them promptly once available.

The primary impact of CVE-2025-64786 is on the integrity of documents processed by Adobe Acrobat Reader. An attacker with local access could bypass cryptographic signature verification, potentially modifying signed documents or injecting unauthorized content without detection. This undermines trust in digitally signed documents, which are widely used in European organizations for contracts, compliance, and official communications. While confidentiality and availability are not directly affected, the integrity breach could lead to legal, regulatory, or reputational consequences if altered documents are accepted as authentic. For European organizations, especially those in regulated industries such as finance, healthcare, and government, this vulnerability could facilitate fraud or data tampering. The lack of user interaction requirement increases the risk in environments where local access is possible, such as shared workstations or compromised endpoints. However, the low CVSS score and absence of known exploits suggest the immediate risk is limited. Still, the widespread use of Acrobat Reader in Europe means that even a low-severity vulnerability can have broad implications if exploited.

1. Monitor Adobe’s official security advisories and apply patches promptly once they are released to address CVE-2025-64786. 2. Restrict local access to systems running vulnerable versions of Acrobat Reader to trusted users only, minimizing the risk of local exploitation. 3. Implement strict file system permissions to limit write access to sensitive documents and directories where signed PDFs are stored or processed. 4. Employ endpoint detection and response (EDR) solutions to monitor for unusual file modifications or suspicious activities related to Acrobat Reader processes. 5. Educate users about the importance of verifying document authenticity through multiple channels, especially for critical transactions. 6. Consider using alternative PDF readers with robust signature verification if patching is delayed. 7. Regularly audit and validate digital signatures on critical documents to detect any unauthorized changes. 8. Incorporate document integrity checks into business workflows to catch tampering early.