CVE-2026-55248Network attack vectorHinoki check available

Service interruption, SSRF, and XSS via RSS portlet

Published Aug 28, 2026 · Updated Aug 28, 2026

RSS portlet flaws in Plone plone.app.portlets allow remote authenticated users to interrupt service, probe internal services, or run script. RSSFeed._retrieveFeed downloads unbounded response bodies into the FEED_DATA memory cache, weak URL validation permits internal destinations, and _buildItemDict retains JavaScript item links. Exploitation requires a member who can add an RSS portlet; affected releases are before 5.0.8, 6.0.0 through 6.0.3, and 7.0.0 through 7.0.1.

CVSS severity9.1
Critical
EPSS probability0.32%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

RSS portlet flaws in Plone plone.app.portlets allow remote authenticated users to interrupt service, probe internal services, or run script. RSSFeed._retrieveFeed downloads unbounded response bodies into the FEED_DATA memory cache, weak URL validation permits internal destinations, and _buildItemDict retains JavaScript item links. Exploitation requires a member who can add an RSS portlet; affected releases are before 5.0.8, 6.0.0 through 6.0.3, and 7.0.0 through 7.0.1.

The record

CVE
CVE-2026-55248
Published
Aug 28, 2026
Updated
Aug 28, 2026
Vendor
Plone
Product
plone.app.portlets
Classifications
CWE-400, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 28, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 28, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 5.0.8
  2. Affected versionversion=>= 6.0.0, < 6.0.4
  3. Affected versionversion=>= 7.0.0, < 7.0.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Plone · plone.app.portletsversion=< 5.0.8; version=>= 6.0.0, < 6.0.4; version=>= 7.0.0, < 7.0.2

Published CVSS scores

9.1GitHubCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-400Uncontrolled Resource Consumption
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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