CVE-2026-1760 is a medium-severity HTTP request smuggling vulnerability identified in SoupServer, a component used in Red Hat Enterprise Linux 10. The flaw stems from inconsistent interpretation and improper handling of HTTP requests that include both Transfer-Encoding: chunked and Connection: keep-alive headers. According to RFC 9112, the server should close the connection after processing such requests, but SoupServer fails to do so. This failure enables a remote, unauthenticated attacker to send specially crafted HTTP requests that 'smuggle' additional requests through the same persistent connection. The consequence is that the server processes unintended requests, which can lead to denial-of-service (DoS) conditions by exhausting server resources or causing unexpected behavior. The vulnerability does not allow attackers to compromise confidentiality or integrity directly but impacts availability. Exploitation requires no authentication or user interaction, and the attack surface includes any externally accessible SoupServer instances running on Red Hat Enterprise Linux 10. Although no known exploits are reported in the wild, the vulnerability's nature makes it a concern for environments exposed to untrusted networks. The CVSS 3.1 base score of 5.3 reflects the medium severity, considering the network attack vector, low complexity, and no privileges or user interaction required. The vulnerability highlights the importance of strict adherence to HTTP protocol standards and robust request parsing to prevent request smuggling attacks.

For European organizations, the primary impact of CVE-2026-1760 is on service availability. Exploitation can lead to denial-of-service conditions, potentially disrupting business-critical applications and services hosted on Red Hat Enterprise Linux 10 systems using SoupServer. This could affect web-facing services, internal APIs, or microservices relying on HTTP communication. While confidentiality and integrity are not directly compromised, service disruption can lead to operational downtime, loss of productivity, and reputational damage. Organizations in sectors such as finance, healthcare, government, and critical infrastructure that depend on high availability and robust service continuity are particularly vulnerable. Additionally, the attack could be leveraged as part of a multi-stage attack chain, where DoS conditions serve as a distraction or facilitate further exploitation. The medium severity score suggests moderate urgency, but the ease of exploitation and lack of required authentication increase the risk profile for exposed systems. European entities with internet-facing Red Hat Enterprise Linux 10 deployments should assess exposure and prioritize remediation to maintain service reliability.

To mitigate CVE-2026-1760, European organizations should implement the following specific measures: 1) Apply official patches or updates from Red Hat as soon as they become available to correct the SoupServer request handling logic. 2) If patches are not immediately available, consider deploying web application firewalls (WAFs) or reverse proxies that can detect and block malformed HTTP requests containing conflicting Transfer-Encoding and Connection headers. 3) Conduct network-level filtering to restrict access to SoupServer instances only to trusted networks or VPNs, minimizing exposure to untrusted external sources. 4) Implement strict HTTP header validation and logging to detect anomalous request patterns indicative of request smuggling attempts. 5) Regularly audit and monitor server logs for signs of persistent connection misuse or unexpected request sequences. 6) Employ rate limiting and connection throttling to reduce the impact of potential DoS attacks exploiting this vulnerability. 7) Educate security teams about HTTP request smuggling techniques to improve detection and incident response capabilities. 8) Review and harden HTTP server configurations to ensure compliance with RFC 9112 and related standards. These targeted actions go beyond generic advice by focusing on immediate protective controls and detection strategies tailored to the nature of this vulnerability.