A security flaw exists in Yelp's yelp-xsl component due to an overly permissive Content Security Policy implementation. A malicious Flatpak application can exploit this by opening crafted help content through the OpenURI portal, embedding untrusted CSS stylesheets within structured SVG documents. This bypasses Flatpak sandbox isolation, enabling Yelp to evaluate local XML inclusions and disclose arbitrary user-readable host files via remote CSS resource requests. The vulnerability affects Red Hat Enterprise Linux versions 8 and 9 prior to the fixed releases. Red Hat has issued security advisories and updates to address this issue.

The vulnerability allows unauthorized disclosure of sensitive local files to a malicious Flatpak application, potentially exposing confidential user data. The CVSS score of 7.1 indicates a high severity impact with confidentiality compromised but no integrity or availability impact. There are no known exploits in the wild at this time.

Red Hat has released official security updates that fix this vulnerability. Users should apply the provided patches for Yelp and yelp-xsl as detailed in Red Hat advisories RHSA-2026:47177 and RHSA-2026:47178. The advisories include instructions for updating affected Red Hat Enterprise Linux 8 and 9 systems. Applying these updates fully mitigates the vulnerability.