CVE-2026-55248 json
plone.app.portlets: Denial of service via RSS feed portlet
published 2026-08-28 2 mo ago modified 2026-09-10 1 mo ago also GHSA-x5g3-w747-2h8q , PYSEC-2026-3884 , EUVD-2026-67864
- cvss
- 9.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 38%
- public exploits
- 0
- none known
Summary
plone.app.portlets provides portlets and a Plone-specific user interface for plone.portlets. Prior to 5.0.8, 6.0.4, and 7.0.2, a member who can add an RSS portlet can set its feed URL to a very large response, causing src/plone/app/portlets/portlets/rss.py to download and retain excessive data in memory and deny service. The same RSS URL handling accepts internal hosts, IP addresses, single-word domains, and explicit ports, allowing server-side requests that can probe internal network services and open ports. A malicious feed item can also supply a JavaScript URL that is retained as the item link and can execute script when used by a victim. The affected logic includes _rss_feed_url_validator, _normal_url_validator, RSSFeed._retrieveFeed, RSSFeed._buildItemDict, and the FEED_DATA in-memory cache. This issue is fixed in versions 5.0.8, 6.0.4, and 7.0.2.
Patch / fix
- pypi plone-app-portlets 5.0.8, 6.0.4, 7.0.2
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2 mo ago
Exploit prediction
0.44% chance of exploitation in the next 30 days, higher than 38% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 9.1 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:H |
| GitHub | 3.1 | 9.1 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:H |
| OSV | 3.1 | 9.1 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | plone-app-portlets | >=7.0.0, <7.0.2 >=6.0.0, <6.0.4 <5.0.8 |
7.0.2 6.0.4 5.0.8 |
Affected products
- plone plone.app.portlets
Classification
- Weakness
-
- CWE-400 Uncontrolled Resource Consumption
References
-
github.com
/plone/plone.app.portlets/commit/09da52ef7b297daa8e0cfd2361e47c37d9b073ad
web
-
github.com
/plone/plone.app.portlets/commit/9f16b6fb10211916686c6c346ea174bf517e3fbd
web
-
github.com
/plone/plone.app.portlets/commit/a3b2c2887165b308cd915cbb87b8276f90a76680
web
-
github.com
/plone/plone.app.portlets/commit/df5e256baee55083cbd6b9a2623675d4cb26b6cd
web
-
github.com
/plone/plone.app.portlets/security/advisories/GHSA-x5g3-w747-2h8q
web
-
github.com
/plone/plone.app.portlets
package
-
pypi.org
/project/plone-app-portlets
package
-
github.com
/advisories/GHSA-x5g3-w747-2h8q
advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-55248
advisory
Sources
- CVE List CVE-2026-55248
- GitHub Advisory GHSA-x5g3-w747-2h8q
- NVD CVE-2026-55248
- OSV PYSEC-2026-3884
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