CVE-2012-5506: Denial of Service Vulnerability in Plone
Summary
CVE-2012-5506: python_scripts.py in Plone before 4.2.3 and 4.3 before beta 1 allows remote attackers to cause a denial of service (infinite loop) via an RSS feed request for a folder the user does not have permission to access. Affects plone across 2 version ranges.
< 4.2.3
>= 4.3a0, < 4.3b1
Fixed in 4.2.3 or 4.3b1, depending on the release line you run. How to fix ↓
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Background
Plone is an open-source content management system built on top of the Zope application server. It provides a user-friendly interface for managing websites and supports various features such as content creation, collaboration, and workflow management. Plone is widely used in both small and large organizations for building secure and scalable web applications. However, versions prior to 4.2.3 and 4.3 beta 1 are vulnerable to a denial of service (infinite loop) attack.
Vulnerability Detail
The vulnerability (CVE-2012-5506) in Plone allows remote attackers to cause a denial of service by sending an RSS feed request for a folder that the user does not have permission to access. This triggers an infinite loop in the python_scripts.py file, leading to excessive resource consumption and potentially crashing the server. The issue can be exploited by an unauthenticated attacker, and it can result in a complete service disruption for affected Plone installations.
How To Fix
Latest published version: 6.2.2 as of 23 Oct 2026
pip install --upgrade "plone==6.2.2"Upgrading to it may include breaking changes; the versions below are the minimum fixed release for this vulnerability.
If you can't move to the latest
The minimum fixed version depends on the release line you run.
-
< 4.2.34.2.3pip install --upgrade "plone==4.2.3" -
>= 4.3a0, < 4.3b14.3b1pip install --upgrade "plone==4.3b1"
Tip — Not sure which release line you're on? Vulert can find the fix for the version you are using. Scan free →
Workaround
There is no known workaround for this vulnerability. It is essential to apply the official patch or upgrade to a fixed version of Plone to mitigate the risk.
Conclusion
The vulnerability in Plone (CVE-2012-5506) allows remote attackers to cause a denial of service by triggering an infinite loop in the python_scripts.py file. To mitigate the risk, it is crucial to upgrade to Plone version 4.2.3 or later. For further assistance or support in vulnerability remediation, please contact DevNack.com.
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FAQ
The vulnerability allows remote attackers to cause a denial of service, potentially leading to a complete service disruption for affected Plone installations.
Yes, the vulnerability can be exploited remotely by sending a specially crafted RSS feed request.
The only known mitigation is to upgrade to Plone version 4.2.3 or later, which includes a fix for this vulnerability.
No, authentication is not required. An unauthenticated attacker can exploit this vulnerability.
There is no publicly available exploit for this vulnerability at the time of this report.
References
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