CVE-2026-55648 FreeRDP CVE debrief

Who should care

Organizations using RemoteApp clients with FreeRDP library versions prior to 3.27.0 should review and update their installations to prevent potential exploitation. This includes reviewing the current version of FreeRDP in use, assessing the potential impact of the vulnerability, and implementing compensating controls if necessary. Security teams and vulnerability management teams should also be aware of the potential risks and take steps to mitigate them. Additionally, operators and platform administrators should be informed of the vulnerability and its potential impact on their systems. This vulnerability may require additional monitoring and review of RDP activity to detect potential exploitation attempts. Affected product deployments should be identified and prioritized for remediation based on risk and exposure. Security teams should verify that all affected assets are remediated or have compensating controls in place. This may involve coordination with multiple teams, including IT operations, security, and compliance. The vulnerability highlights the importance of keeping software up to date and having robust vulnerability management processes in place. It also emphasizes the need for proactive measures to detect and respond to potential security incidents. By taking these steps, organizations can reduce the risk of exploitation and protect their systems from potential attacks. The vulnerability is a reminder of the importance of secure coding practices and thorough testing to prevent similar issues in the future. Organizations should also consider implementing additional security controls, such as network segmentation and access controls, to further reduce the risk of exploitation. By prioritizing remediation and implementing compensating controls, organizations can minimize the risk of exploitation and protect their systems from potential attacks. This vulnerability is a good example of the importance of collaboration between security teams, IT operations, and compliance teams to ensure that vulnerabilities are properly managed and remediated. The vulnerability also highlights the need for ongoing monitoring and review of system security to detect and A

Technical summary

The freerdp_image_copy_from_icon_data function in libfreerdp/codec/color.c performs a 32-bit arithmetic calculation for image data size, which can wrap for large dimensions and 32 bits per pixel. This allows a malicious RDP server to send a RAIL TS_ICON_INFO update that bypasses the source bounds check, potentially leading to code execution on affected clients. The issue is fixed in version 3.27.0. xfreerdp has a caller-side mitigation. RemoteApp clients using the vulnerable library path are affected.

Defensive priority

Remote Desktop Protocol clients using FreeRDP library versions prior to 3.27.0 require defensive review and potential updates to prevent potential code execution.

Recommended defensive actions

• Review and update FreeRDP library to version 3.27.0 or later
• Implement compensating controls, such as validating RDP server connections
• Monitor for suspicious RDP activity
• Inventory and assess affected RemoteApp clients
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed
• Check relevant monitoring, detection, and logs for exposed assets that need extra review

Evidence notes

The CVE record indicates a medium-severity vulnerability in FreeRDP, a free implementation of the Remote Desktop Protocol, prior to version 3.27.0. The issue involves an integer wrap in the calculation of image data size, allowing a malicious RDP server to potentially execute arbitrary code on affected clients. The NVD entry is currently Medium.

Official resources