CVE-2026-67289
Description
A flaw was found in FreeRDP. A malicious or compromised Remote Desktop Protocol (RDP) server can exploit this vulnerability to inject arbitrary headers or requests into an HTTP proxy CONNECT request. This occurs because FreeRDP does not properly validate control characters in the server-controlled RDP redirection TargetNetAddress field, which is then used without filtering. This injection could allow an attacker to manipulate the proxy's behavior or bypass certain network security policies.
Statement
Moderate: This client-side vulnerability in FreeRDP allows for HTTP proxy request injection. Exploitation requires a FreeRDP client to be configured to use an HTTP proxy and to connect to a malicious or compromised RDP server, which then sends a crafted redirection PDU. This limits the attack surface to specific client configurations and interactions with untrusted RDP endpoints.
Mitigation
To mitigate this issue, FreeRDP clients should avoid connecting to untrusted RDP servers when configured to use an HTTP proxy. Alternatively, if connecting to potentially untrusted RDP servers, disable the HTTP proxy configuration for FreeRDP.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5 | N/A | 9.8 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | High | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | Required | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | Low | N/A | High |
| Integrity Impact | Low | N/A | High |
| Availability Impact | Low | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:L
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Understanding the Weakness (CWE)
Integrity
Technical Impact: Modify Application Data
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
