CVE-2025-10148

A flaw was found in curl. The use of a predictable WebSocket mask pattern allows a malicious server to induce traffic that an intermediary proxy (whether configured or transparent) will misinterpret as a standard HTTP request. This confusion leads to a cache poisoning attack, where the proxy stores the server's malicious content and serves it to all users of that proxy.

To exploit this issue, a curl application must be communicating through a defective proxy that confuses a WebSocket for HTTP traffic. Additionally, this flaw requires the traffic to be done using clear text HTTP / WebSocket (ws://) and not over TLS (wss://).

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.