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CVE-2026-55247

CVE-2026-55247 · plone.app.event: Denial of service via iCalendar import

This page contains facts from public vulnerability sources. Check the original advisory before updating.

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.

CVSS 9.1 · Critical · EPSS 0.4% · Fix available

Published
Updated

Stack: python

Affected products and versions

  • plone.app.event

    Versions
    • < 5.2.4: Affected
    • >= 6.0.0, < 6.0.1: Affected

    No fix published

  • plone-app-event PyPI

    Versions
    • 1.0
    • 1.0.1
    • 1.0.2
    • 1.0.3
    • 1.0.4
    • 1.0.5
    • 1.0.6
    • 1.0a1
    • 1.0a2
    • 1.0b1
    • 1.0b2
    • 1.0b3
    • 1.0b4
    • 1.0b5
    • 1.0b6
    • 1.0b7
    • 1.0b8
    • 1.0rc1
    • 1.0rc2
    • 1.0rc3
    • 1.1
    • 1.1.1
    • 1.1.10
    • 1.1.11
    • 1.1.12
    • 1.1.13
    • 1.1.2
    • 1.1.3
    • 1.1.4
    • 1.1.5
    • 1.1.6
    • 1.1.7
    • 1.1.8
    • 1.1.a1
    • 1.1b1
    • 1.2
    • 1.2.1
    • 1.2.2
    • 1.2.3
    • 1.2.4
    • 1.2.5
    • 1.2.6
    • 1.2.7
    • 2.0
    • 2.0.1
    • 2.0.10
    • 2.0.11
    • 2.0.12
    • 2.0.13
    • 2.0.14
    • 2.0.15
    • 2.0.2
    • 2.0.3
    • 2.0.4
    • 2.0.5
    • 2.0.6
    • 2.0.7
    • 2.0.8
    • 2.0.9
    • 2.0a1
    • 2.0a10
    • 2.0a11
    • 2.0a12
    • 2.0a13
    • 2.0a2
    • 2.0a3
    • 2.0a4
    • 2.0a5
    • 2.0a6
    • 2.0a7
    • 2.0a8
    • 2.0a9
    • 2.0b1
    • 2.0b2
    • 3.0
    • 3.0.1
    • 3.0.2
    • 3.0.3
    • 3.0.4
    • 3.0.5
    • 3.0.6
    • 3.0.7
    • 3.1
    • 3.1.1
    • 3.2.0
    • 3.2.1
    • 3.2.10
    • 3.2.11
    • 3.2.12
    • 3.2.13
    • 3.2.14
    • 3.2.2
    • 3.2.3
    • 3.2.4
    • 3.2.5
    • 3.2.6
    • 3.2.7
    • 3.2.8
    • 3.2.9
    • 4.0.0
    • 4.0.0a1
    • 4.0.0a2
    • 4.0.0a3
    • 4.0.0a4
    • 4.0.0a5
    • 4.0.0a6
    • 4.0.0a7
    • 4.0.0a8
    • 4.0.0a9
    • 4.0.0b1
    • 5.0.0
    • 5.0.1
    • 5.1.0
    • 5.1.1
    • 5.1.2
    • 5.1.3
    • 5.1.4
    • 5.1.5
    • 5.1.6
    • 5.1.7
    • 5.1.8
    • 5.2.0
    • 5.2.1
    • 5.2.2
    • 5.2.3
    Affected ranges
    • ECOSYSTEM: < 5.2.4

    Update to 5.2.4

  • plone-app-event PyPI

    Versions
    • 6.0.0
    • 6.0.0a1
    • 6.0.0a2
    Affected ranges
    • ECOSYSTEM: ≥ 6.0.0a1, < 6.0.1

    Update to 6.0.1

  • plone-app-event PyPI

    Versions
    • 1.0
    • 1.0.1
    • 1.0.2
    • 1.0.3
    • 1.0.4
    • 1.0.5
    • 1.0.6
    • 1.0a1
    • 1.0a2
    • 1.0b1
    • 1.0b2
    • 1.0b3
    • 1.0b4
    • 1.0b5
    • 1.0b6
    • 1.0b7
    • 1.0b8
    • 1.0rc1
    • 1.0rc2
    • 1.0rc3
    • 1.1
    • 1.1.1
    • 1.1.10
    • 1.1.11
    • 1.1.12
    • 1.1.13
    • 1.1.2
    • 1.1.3
    • 1.1.4
    • 1.1.5
    • 1.1.6
    • 1.1.7
    • 1.1.8
    • 1.1.a1
    • 1.1b1
    • 1.2
    • 1.2.1
    • 1.2.2
    • 1.2.3
    • 1.2.4
    • 1.2.5
    • 1.2.6
    • 1.2.7
    • 2.0
    • 2.0.1
    • 2.0.10
    • 2.0.11
    • 2.0.12
    • 2.0.13
    • 2.0.14
    • 2.0.15
    • 2.0.2
    • 2.0.3
    • 2.0.4
    • 2.0.5
    • 2.0.6
    • 2.0.7
    • 2.0.8
    • 2.0.9
    • 2.0a1
    • 2.0a10
    • 2.0a11
    • 2.0a12
    • 2.0a13
    • 2.0a2
    • 2.0a3
    • 2.0a4
    • 2.0a5
    • 2.0a6
    • 2.0a7
    • 2.0a8
    • 2.0a9
    • 2.0b1
    • 2.0b2
    • 3.0
    • 3.0.1
    • 3.0.2
    • 3.0.3
    • 3.0.4
    • 3.0.5
    • 3.0.6
    • 3.0.7
    • 3.1
    • 3.1.1
    • 3.2.0
    • 3.2.1
    • 3.2.10
    • 3.2.11
    • 3.2.12
    • 3.2.13
    • 3.2.14
    • 3.2.2
    • 3.2.3
    • 3.2.4
    • 3.2.5
    • 3.2.6
    • 3.2.7
    • 3.2.8
    • 3.2.9
    • 4.0.0
    • 4.0.0a1
    • 4.0.0a2
    • 4.0.0a3
    • 4.0.0a4
    • 4.0.0a5
    • 4.0.0a6
    • 4.0.0a7
    • 4.0.0a8
    • 4.0.0a9
    • 4.0.0b1
    • 5.0.0
    • 5.0.1
    • 5.1.0
    • 5.1.1
    • 5.1.2
    • 5.1.3
    • 5.1.4
    • 5.1.5
    • 5.1.6
    • 5.1.7
    • 5.1.8
    • 5.2.0
    • 5.2.1
    • 5.2.2
    • 5.2.3
    • 6.0.0
    • 6.0.0a1
    • 6.0.0a2
    Affected ranges
    • ECOSYSTEM: < 5.2.4 ∪ ≥ 6.0.0a1, < 6.0.1

    Update to 5.2.4; Update to 6.0.1

Original sources

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