CVE-2026-57576: 
Python 취약성 분석 및 완화

CVE-2026-57576 is a Denial of Service (DoS) vulnerability affecting Plone's plone.app.dexterity content-type framework and plone.app.contenttypes package. An authenticated user can create content items with excessively long titles, descriptions, or uploaded file names, causing the Plone CMS to become unresponsive and rendering the affected content difficult or impossible to edit or delete. Affected versions include plone.app.dexterity through 3.2.2, 4.0.0–4.1.2, and 5.0.0, and plone.app.contenttypes through 3.0.11, 4.0.0–4.0.9, and 5.0.0. The vulnerability was first published on June 23, 2026, and added to the GitHub Advisory Database on September 23, 2026. It carries a CVSS v3.1 base score of 6.5 (Medium) (GitHub Advisory).

The root cause is uncontrolled resource consumption (CWE-400) due to the absence of maximum length constraints on the title, description, and uploaded file name fields in Plone's Dexterity-based content types. When an authenticated user submits content with arbitrarily large field values, Plone processes and stores the data without enforcing any upper bound, causing the application UI to become unwieldy or unresponsive when rendering or editing the content. The fix enforces a max_length of 1,024 characters for titles and 10,000 characters for descriptions in the schema definitions for file and image content types, and introduces a MAX_TITLE_LENGTH constant in plone.app.dexterity that plone.app.contenttypes also references (GitHub Advisory, Contenttypes Commit). No authentication bypass or privilege escalation is required; any user with content-creation permissions can trigger the issue.

Successful exploitation causes the Plone application to become unresponsive, effectively denying service to all users of the affected instance. The created content with oversized fields may be persistently difficult or impossible to edit or delete through the standard UI, potentially requiring administrative intervention at the database level to remediate. There is no impact on confidentiality or data integrity beyond the availability disruption; the vulnerability is scoped to the affected Plone instance and does not facilitate lateral movement or data exfiltration (GitHub Advisory).

No public proof-of-concept exploit code has been published, and there is no evidence of in-the-wild exploitation at this time (GitHub Advisory). The EPSS score is approximately 0.762% (54th percentile), indicating a low but non-negligible probability of exploitation within 30 days. The vulnerability is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog. Exploitation requires only low-privilege authenticated access, making it accessible to any registered Plone user, which lowers the practical barrier despite the absence of known weaponization.

1. Authenticate: Log in to the target Plone instance with any account that has content-creation permissions (e.g., a standard contributor role).
2. Navigate to content creation: Access the "Add content" interface for a supported content type such as a Page, File, or Image.
3. Submit oversized field values: Populate the title field with a string exceeding 1,024 characters and/or the description field with a string exceeding 10,000 characters, or upload a file with an excessively long filename (e.g., a string of thousands of characters).
4. Save the content: Submit the form. The Plone backend accepts and stores the oversized data without validation.
5. Trigger DoS: Subsequent attempts by any user (including administrators) to view, edit, or delete the created content cause the Plone UI to become unresponsive or hang, resulting in a denial of service for the affected content and potentially the broader application (GitHub Advisory).

• Logs: Plone access logs showing POST requests to content-creation endpoints (e.g., @@add, createObject) with unusually large request body sizes; application logs showing timeouts or errors when rendering or editing specific content items.
• Application Behavior: Plone UI becoming unresponsive or timing out when accessing specific content items; administrator reports of content that cannot be edited or deleted through the standard interface.
• Database/Storage: Content objects in the ZODB with title or description field values significantly exceeding 1,024 or 10,000 characters respectively, or file objects with filenames of unusual length.

Upgrade to the patched versions as soon as possible: plone.app.dexterity 3.2.3 (Plone 6.0), 4.1.3 (Plone 6.1), or 5.0.1 (Plone 6.2); and plone.app.contenttypes 3.0.12, 4.0.10, or 5.0.1. The Plone/Zope Security Team has confirmed there are no known configuration-based workarounds. As an interim measure, administrators should restrict content-creation permissions to trusted users only and monitor application responsiveness for signs of exploitation (GitHub Advisory).

The Plone/Zope Security Team noted that the fixes required careful development to avoid disrupting corner cases, and chose to develop the patches publicly to allow community review and early feedback — an unusual but transparent approach to security remediation. The vulnerability was responsibly reported by Aldin Visnjic to the Plone/Zope Security Team (GitHub Advisory). No significant broader media coverage or notable researcher commentary beyond the official advisory has been identified.