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vulnerability / NVI-00014154 / Revision 1

plone.app.portlets vulnerable to denial of service via RSS feed portlet

GitHub lists this reviewed advisory for plone.app.portlets, plone.app.portlets, plone.app.portlets. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.

source listedactiveGHSA-x5g3-w747-2h8qCVE-2026-55248

This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.

01 / Meaning

Why it matters

Published affected context helps an owner decide what evidence to gather. This report has not examined your application.

CVSS

9.1 critical

GitHub source severity; exploitability and local consequence require separate evidence.

As of · GitHub Advisory Database

02 / Applicability

The affected context

Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.

plone.app.portlets

source listed
  • >= 7.0.0, <= 7.0.1

### Impact By adding an RSS portlet, and giving this a link to a very large file, a member can cause a denial of service attack, because Plone will use lots of memory. The member could also use different urls to try to get information about the internal network and open port numbers (SSRF). A malicious RSS feed could cause stored XSS, when the url of a feed item is a javascript url. ### Patches The problem has been patched in `plone.app.portlets`. * For Plone 6.2: upgrade to `plone.app.portlets` 7.0.2 * For Plone 6.1: upgrade to `plone.app.portlets` 6.0.4 * For Plone 6.0: upgrade to `plone.app.portlets` 5.0.8 ### Workarounds If upgrading is not immediately possible: - Restrict who can manage portlets: remove the `plone.app.portlets.ManageOwnPortlets` permission from untrusted roles, and limit Manage portlets to trusted administrators (usually this is already restricted to the Manager and Site Administrator roles). - Where the RSS portlet is not needed, unregister it so it cannot be added. This would need to be done by editing a `portlets.xml` in your own code, so it is not a quick fix. ### References This is similar to this [`plone.app.event` vulnerability](https://github.com

GitHub Advisory Database

plone.app.portlets

source listed
  • >= 6.0.0, < 6.0.4

### Impact By adding an RSS portlet, and giving this a link to a very large file, a member can cause a denial of service attack, because Plone will use lots of memory. The member could also use different urls to try to get information about the internal network and open port numbers (SSRF). A malicious RSS feed could cause stored XSS, when the url of a feed item is a javascript url. ### Patches The problem has been patched in `plone.app.portlets`. * For Plone 6.2: upgrade to `plone.app.portlets` 7.0.2 * For Plone 6.1: upgrade to `plone.app.portlets` 6.0.4 * For Plone 6.0: upgrade to `plone.app.portlets` 5.0.8 ### Workarounds If upgrading is not immediately possible: - Restrict who can manage portlets: remove the `plone.app.portlets.ManageOwnPortlets` permission from untrusted roles, and limit Manage portlets to trusted administrators (usually this is already restricted to the Manager and Site Administrator roles). - Where the RSS portlet is not needed, unregister it so it cannot be added. This would need to be done by editing a `portlets.xml` in your own code, so it is not a quick fix. ### References This is similar to this [`plone.app.event` vulnerability](https://github.com

GitHub Advisory Database

plone.app.portlets

source listed
  • < 5.0.8

### Impact By adding an RSS portlet, and giving this a link to a very large file, a member can cause a denial of service attack, because Plone will use lots of memory. The member could also use different urls to try to get information about the internal network and open port numbers (SSRF). A malicious RSS feed could cause stored XSS, when the url of a feed item is a javascript url. ### Patches The problem has been patched in `plone.app.portlets`. * For Plone 6.2: upgrade to `plone.app.portlets` 7.0.2 * For Plone 6.1: upgrade to `plone.app.portlets` 6.0.4 * For Plone 6.0: upgrade to `plone.app.portlets` 5.0.8 ### Workarounds If upgrading is not immediately possible: - Restrict who can manage portlets: remove the `plone.app.portlets.ManageOwnPortlets` permission from untrusted roles, and limit Manage portlets to trusted administrators (usually this is already restricted to the Manager and Site Administrator roles). - Where the RSS portlet is not needed, unregister it so it cannot be added. This would need to be done by editing a `portlets.xml` in your own code, so it is not a quick fix. ### References This is similar to this [`plone.app.event` vulnerability](https://github.com

GitHub Advisory Database

03 / Response

What to do next

  1. investigate

    Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.

    Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database

A fixed release is not deployment evidence.

Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.

04 / Limits

What this report cannot establish

  • Customer inventory, deployment, reachability and exploitation have not been inspected.
Read the collection and interpretation limits ↗

05 / Provenance

Sources you can inspect

Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.

  1. GHSA-x5g3-w747-2h8q ↗

    GitHub Advisory Database · vendor advisory

    Observed . GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.

Public revision history

Only published revisions appear here. Routine fetches do not create a material-change event.

  1. Revision 1 ·

    First indexed by Null; source disclosure date is shown separately.

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The next step is private

Bring the question into your environment.

The connected workflow is a development preview for inventory, contextual matching, owner decisions and evidence-based verification. No system-specific result is generated by this page.

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