CVE-2026-15928

A flaw was found in the XMLRPC-C Library. This reflected cross-site scripting (XSS) vulnerability exists in the error page component. A remote attacker could exploit this by tricking a user into clicking a specially crafted link. Successful exploitation could lead to the execution of malicious scripts in the user's browser, potentially resulting in information disclosure or session hijacking.

This reflected cross-site scripting (XSS) vulnerability relies entirely on client-side interaction through a web browser. Practical exploitation requires a remote attacker to trick a user into clicking a targeted link that passes crafted input to an application displaying the XMLRPC-C error page. If executed, the script runs within the context of the user's browser session, making sensitive session tokens or client-side data accessible to the attacker.

While external CVSSv4 scoring rates this flaw to an 8.2 High, Red Hat bounds the severity to CVSS 7.4 based on explicit CIA triad mechanics. The impact is strictly confined to Confidentiality (C:H) via potential browser-side data disclosure. The flaw carries zero impact on system Integrity (I:N) or Availability (A:N), as it cannot alter server-side application logic, modify stored data, or disrupt underlying XML-RPC services.

Deployments operating strictly as headless backend services, non-interactive daemons, or server-to-server API endpoints—where the XMLRPC-C error component is never exposed or rendered inside a user's web browser—are fundamentally outside the execution boundary of this flaw and remain at zero risk.

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.

To mitigate this issue, ensure that applications utilizing the XMLRPC-C library do not directly expose its error pages to end-users via a web browser. Configure web servers or application frontends to intercept and sanitize or replace error responses originating from XMLRPC-C before they are rendered client-side. Alternatively, restrict XMLRPC-C deployments to backend services that do not present error output in a user-facing web interface.