CVE-2026-55247

Published Aug 28, 2026

Last updated 25 days ago

Overview

AI description

Automated description summarized from trusted sources.

CVE-2026-55247 is a recently reserved vulnerability identifier, with details published on June 23, 2026. This CVE is associated with a Denial of Service (DoS) vulnerability that can be triggered through iCalendar import functionality. The affected component is `plone.app.event`, where the vulnerability allows for a denial of service.

Description: plone.app.event provides the event content type for Plone. Prior to versions 5.2.4 and 6.0.1, the iCalendar import in src/plone/app/event/ical/importer.py accepts insufficiently restricted calendar and event URLs, does not adequately bound downloaded bytes or imported events, and commits work per event. A logged-in editor can make the server request internal network resources or local calendar files, exhaust resources and take the site offline, and store a malicious event URL that executes script in another user's browser. The fix restricts accepted URLs, applies MAXIMUM_ICAL_IMPORT_SIZE_BYTES and MAXIMUM_ICAL_IMPORT_EVENTS limits, uses transaction savepoints, and validates event URLs. This issue is fixed in versions 5.2.4 and 6.0.1.
Source: security-advisories@github.com
NVD status: Deferred

Risk scores

CVSS 3.1

Type: Secondary
Base score: 9.1
Impact score: 5.3
Exploitability score: 3.1
Vector string: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:H
Severity: CRITICAL

Weaknesses

security-advisories@github.com: CWE-400

Hype score: Not currently trending

References