CVE-2025-64787 is a security 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 arises from improper verification of cryptographic signatures (classified under CWE-347), which compromises the integrity checks that ensure the authenticity and unaltered state of PDF documents. This weakness allows an attacker to bypass cryptographic protections designed to prevent unauthorized modifications, thereby gaining limited write access to PDF content or metadata. Notably, exploitation does not require user interaction, increasing the risk of automated or remote attacks. However, the vulnerability's CVSS score is 3.3 (low severity), reflecting limited impact primarily on integrity without affecting confidentiality or availability. There are no known exploits in the wild at this time, and no patches have been linked yet. The vulnerability could be leveraged to alter documents in ways that might mislead recipients or disrupt workflows relying on document authenticity. Given Adobe Acrobat Reader's widespread use in business and government sectors, especially in Europe, this vulnerability poses a risk to document trustworthiness and compliance with regulatory standards that mandate document integrity. The technical root cause is a failure in the cryptographic signature verification process, which should normally prevent unauthorized changes. Attackers exploiting this flaw could bypass these controls, potentially inserting malicious content or falsifying document data.

For European organizations, the primary impact of CVE-2025-64787 lies in the potential compromise of document integrity. This could affect legal, financial, and governmental sectors where PDF documents are used for contracts, official records, and sensitive communications. Unauthorized modifications could lead to misinformation, fraud, or regulatory non-compliance, especially under strict data governance frameworks like GDPR. Although the vulnerability does not directly expose confidential information or disrupt availability, the ability to alter documents without detection undermines trust in digital workflows. Organizations relying heavily on Adobe Acrobat Reader for document handling may face operational risks and reputational damage if exploited. The lack of required user interaction facilitates stealthy exploitation, increasing the threat to automated document processing systems. However, the limited scope of write access and low CVSS score suggest that the overall risk is moderate to low, provided organizations maintain good security hygiene and apply patches promptly once available.

1. Monitor Adobe’s security advisories closely and apply official patches or updates as soon as they are released to address CVE-2025-64787. 2. Implement strict document handling policies that restrict editing permissions on sensitive PDFs, using Adobe Acrobat’s security features or third-party tools. 3. Employ digital signature validation tools that independently verify cryptographic signatures outside of Acrobat Reader to detect tampering. 4. Use endpoint protection solutions capable of detecting anomalous file modifications or unauthorized write attempts on PDF files. 5. Educate users about the importance of verifying document authenticity and encourage reporting of suspicious documents. 6. Consider deploying application whitelisting or sandboxing for Acrobat Reader to limit the impact of potential exploitation. 7. Maintain comprehensive logging and monitoring of document access and modifications to enable rapid incident response. 8. For critical workflows, implement multi-factor verification of document changes involving human oversight to mitigate automated attacks.