CVE-2025-1656 is a heap-based buffer overflow vulnerability identified in Autodesk Revit versions 2023, 2024, and 2025. The vulnerability arises when a maliciously crafted PDF file is linked or imported into the Revit application. Specifically, the vulnerability is triggered by improper handling of PDF content within the application, leading to a heap-based buffer overflow (CWE-122). This type of overflow occurs when data exceeding the allocated heap buffer size is written, potentially overwriting adjacent memory. Exploitation of this vulnerability can result in several adverse outcomes: forced application crashes (denial of service), unauthorized reading of sensitive data from memory, or execution of arbitrary code within the context of the Revit process. The arbitrary code execution risk implies that an attacker could potentially run malicious payloads with the same privileges as the user running Revit, which may lead to further compromise of the host system or network. The vulnerability does not require user authentication but does require user interaction in the form of importing or linking a malicious PDF file into the application. As of the published date (April 15, 2025), no known exploits are reported in the wild, and no patches have been released yet. Autodesk has reserved the CVE and enriched the information with CISA, indicating recognition of the vulnerability's significance. Given the nature of Revit as a widely used Building Information Modeling (BIM) software in architecture, engineering, and construction sectors, this vulnerability poses a notable risk to organizations relying on these workflows.

For European organizations, the impact of CVE-2025-1656 can be significant, especially in sectors such as architecture, engineering, construction, and infrastructure development where Autodesk Revit is heavily utilized. Exploitation could lead to unauthorized disclosure of sensitive design data, intellectual property theft, or disruption of critical design workflows through application crashes. Arbitrary code execution could enable attackers to establish persistence within corporate networks, potentially leading to lateral movement and further compromise of IT infrastructure. This is particularly concerning for organizations involved in critical infrastructure projects or government contracts, where data confidentiality and integrity are paramount. The disruption of BIM workflows could delay project timelines and increase costs. Additionally, the ability to execute code remotely via a crafted PDF file introduces a vector for targeted attacks, including spear-phishing campaigns leveraging malicious documents. The lack of patches at the time of disclosure increases the window of exposure, necessitating immediate mitigations. Given the interconnected nature of European supply chains in construction and engineering, a successful attack could have cascading effects beyond a single organization.

1. Implement strict controls on the handling of PDF files within Autodesk Revit workflows. This includes restricting the import or linking of PDFs from untrusted or unknown sources. 2. Employ network segmentation and application whitelisting to limit the ability of compromised Revit instances to communicate laterally or execute unauthorized processes. 3. Use endpoint detection and response (EDR) solutions to monitor for anomalous behavior indicative of exploitation attempts, such as unexpected crashes or code execution patterns within Revit processes. 4. Educate users about the risks of opening or importing PDFs from external sources and establish policies for verifying file provenance before use. 5. Until patches are available, consider disabling or limiting the functionality that allows PDF import/linking in Revit if feasible, or use virtualized environments for handling untrusted files. 6. Monitor Autodesk and CISA advisories closely for patch releases and apply updates promptly once available. 7. Conduct regular backups of critical project data to enable recovery in case of disruption. 8. Integrate PDF file scanning with advanced threat protection tools to detect and block maliciously crafted PDFs before they reach end users.