CVE-2025-11021 is a vulnerability identified in the libsoup HTTP library, a widely used component in GNOME and other Linux-based applications for handling HTTP communications. The flaw arises from improper handling of cookie expiration dates, where specially crafted cookie data can cause the library to perform an out-of-bounds read operation on memory. This out-of-bounds read does not crash the application but may disclose sensitive information residing in adjacent memory areas, leading to potential leakage of confidential data. The vulnerability can be exploited remotely without requiring any authentication or user interaction, as it is triggered during normal HTTP cookie processing. The affected product explicitly includes Red Hat Enterprise Linux 10, which bundles libsoup as part of its GNOME stack and other networked applications. The CVSS v3.1 score of 7.5 reflects a high severity due to the vulnerability's ability to compromise confidentiality with low attack complexity and no privileges required. Although no public exploits have been reported yet, the nature of the flaw makes it a candidate for future exploitation, especially in environments processing untrusted HTTP cookies. The vulnerability is particularly relevant for applications that rely on libsoup for web communication, including browsers, network clients, and embedded systems running Linux distributions that incorporate this library.

For European organizations, the primary impact of CVE-2025-11021 is the potential unauthorized disclosure of sensitive information from memory, which could include credentials, session tokens, or other confidential data processed by applications using libsoup. This confidentiality breach can facilitate further attacks such as session hijacking, privilege escalation, or data exfiltration. Since the vulnerability can be exploited remotely without authentication, exposed network-facing services using libsoup are at risk. Organizations in sectors with high reliance on Red Hat Enterprise Linux 10 and GNOME-based environments—such as government, finance, and critical infrastructure—may face increased risk. The exposure of sensitive data could lead to regulatory compliance issues under GDPR, reputational damage, and operational disruptions. The lack of impact on integrity and availability limits the scope to confidentiality, but the ease of exploitation and broad usage of libsoup amplify the threat. European entities must be vigilant in patch management and network monitoring to mitigate potential exploitation attempts.

To mitigate CVE-2025-11021, organizations should promptly apply security patches provided by Red Hat and other Linux distributors that address the libsoup cookie handling flaw. In the absence of immediate patches, consider deploying network-level controls such as web application firewalls (WAFs) to detect and block suspicious HTTP cookie headers with malformed expiration dates. Conduct thorough audits of applications and services that utilize libsoup to identify exposure points and reduce unnecessary network access. Implement strict input validation and sanitization for HTTP cookies where possible. Monitor network traffic for anomalous cookie patterns that could indicate exploitation attempts. Additionally, employ memory protection mechanisms and enable security features such as Address Space Layout Randomization (ASLR) to reduce the risk of memory disclosure. Regularly review and update incident response plans to include scenarios involving memory disclosure vulnerabilities. Finally, maintain awareness of vendor advisories and threat intelligence feeds for emerging exploit information.