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Pulpcore: python-pulpcore: stored cross-site scripting via inline rendering of uploaded html/svg content

Published Sep 1, 2026

Description

A flaw was found in pulpcore's content serving application. Files uploaded to Pulp file-type repositories are served with their original content type (e.g., text/html for .html files, image/svg+xml for .svg files) and without a Content-Disposition: attachment header when using local filesystem storage. An authenticated user or attacker with content upload permissions can upload a specially crafted HTML or SVG file containing JavaScript, which executes in the browser of any user who visits the file URL, resulting in stored cross-site scripting (XSS) in the context of the host application.

Affected products

Remediation

Vendor solution

If immediate update is not possible, administrators can add security headers to the Apache reverse proxy configuration for the /pulp/content/ path. On Satellite, add the following to the Apache configuration (e.g., via a custom .conf file in /etc/httpd/conf.d/ or via a Puppet override):

``` <Location /pulp/content> Header set Content-Disposition "attachment" Header set X-Content-Type-Options "nosniff" Header set Content-Security-Policy "default-src 'none'; sandbox" </Location> ``` This forces all content downloads rather than inline rendering, and blocks script execution even if Content-Disposition is somehow bypassed.

After applying, restart Apache: ```systemctl restart httpd``` Alternatively, restrict file upload permissions in Satellite to only trusted users who require content management capabilities.

Red Hat statement

Red Hat Product Security has assessed this issue as a Moderate severity vulnerability. This vulnerability affects pulpcore's content serving application, which is an aiohttp process separate from the Django REST API. The confidentiality and integrity impact is limited because the session cookie in the host application (Foreman/Satellite) is set with the HttpOnly attribute, which prevents direct session token theft via JavaScript. The attacker's script can read visible page content and make authenticated API requests on behalf of the victim through the browser, but cannot exfiltrate the session itself or gain persistent access beyond the victim's active browser session. There is no availability impact. ``` In Red Hat Satellite, the /pulp/content/ path shares the same origin (protocol, hostname, and port) as the Satellite web UI, making the XSS effective against Satellite sessions. ``` ``` Ansible Automation Platform and RHUI also ship pulpcore, but they do not use pulp_file repositories and therefore are not affected by this vulnerability. ```

Red Hat mitigation

If immediate update is not possible, administrators can add security headers to the Apache reverse proxy configuration for the /pulp/content/ path. On Satellite, add the following to the Apache configuration (e.g., via a custom .conf file in /etc/httpd/conf.d/ or via a Puppet override): ``` <Location /pulp/content> Header set Content-Disposition "attachment" Header set X-Content-Type-Options "nosniff" Header set Content-Security-Policy "default-src 'none'; sandbox" </Location> ``` This forces all content downloads rather than inline rendering, and blocks script execution even if Content-Disposition is somehow bypassed. After applying, restart Apache: ```systemctl restart httpd``` Alternatively, restrict file upload permissions in Satellite to only trusted users who require content management capabilities.

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Sources
CVE.org / MITRE
Status PUBLISHED
Assigner redhat
Published Sep 1, 2026
Updated Sep 17, 2026
Reserved Sep 1, 2026
CISA Vulnrichment
Updated Sep 1, 2026
NVD
Status Awaiting Analysis
Modified Sep 1, 2026
Red Hat
Severity Moderate
Public date Sep 1, 2026