CVE-2026-67289: FreeRDP before 3.29.0 HTTP Proxy Request Injection via Redirection

Vulnerability summary

CVE-2026-67289 is a critical (CVSS 9.8) vulnerability in freerdp. EPSS estimates a 0.43% chance of exploitation in the next 30 days, higher than 37.1% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 01-08-2026
   PublishedVulnerability first disclosed.
2. 05-08-2026
   Last modifiedVulnerability information updated.

Description

FreeRDP before 3.29.0 (affected versions <= 3.28.0) does not validate CRLF and control characters in the server-controlled RDP redirection TargetNetAddress field. This value is copied into the client's ServerHostname and, when the client connects through an HTTP proxy, is written directly into the proxy CONNECT request line and Host header by http_proxy_connect() without filtering. A malicious or compromised RDP server can send a crafted redirection PDU containing embedded control characters to inject arbitrary headers/requests into the HTTP proxy CONNECT request.

• CWE-113Improper Neutralization of CRLF Sequences in HTTP HeadersThe product receives data from an HTTP agent/component (e.g., web server, proxy, browser, etc.), but it does not neutralize or incorrectly neutralizes CR and LF characters before the data is included in outgoing HTTP headers.