Medium

plone.app.dexterity has a Denial of Service due to excessive title or description length

  • Disclosed: 23.09.2026
  • Updated: 11.10.2026 15:18

Impact

When creating content with a very large title or description field, Plone can become unresponsive. Even if the content loads, it can be hard to edit or delete, because the UI is unwieldy.

Patches

The problem has been patched in plone.app.dexterity.

  • On Plone 6.2, upgrade to plone.app.dexterity 5.0.1.
  • On Plone 6.1, upgrade to plone.app.dexterity 4.1.3.
  • On Plone 6.0, upgrade to plone.app.dexterity 3.2.3.

Another part of this problem has been patched in plone.app.contenttypes. See this advisory.

Workarounds

There are no known workarounds.

This problem was responsibly reported by Aldin Visnjic to the Plone/Zope Security Team. Thank you!

Note: The Plone/Zope Security team felt that the kind of fixes that were needed could be disruptive in corner cases if they were not careful. So they decided to develop the fixes publicly, giving the whole community the chance the review, and giving them the benefit from early feedback.

Affected software

Click a technology to see all vulnerabilities affecting it.

PlatformPackageVulnerable versionsFixed in
Python (PyPI) plone-app-dexterity >= 5.0.0, < 5.0.1, >= 4.0.0, < 4.1.3, < 3.2.3 5.0.1, 4.1.3, 3.2.3

References

CVSS score 6.5/10
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE)
CWE-400
Platform
Python (PyPI)
Package
plone-app-dexterity
Disclosed
23.09.2026
Updated
11.10.2026 15:18

Sources and licenses

OSV / GitHub Advisory Database - PYSEC-2026-4137 - PyPA Advisory Database; CC BY 4.0

OSV / GitHub Advisory Database - GHSA-5426-92w4-wvhv - CC BY 4.0

Vulnerability history: plone-app-dexterity

All published vulnerabilities of this package (Python (PyPI)), newest first. Shows whether this is a one-off slip or a package that needs watching.

Total entries
4
First → latest
12.2020 09.2026
Without a fix
0
Exploited in attacks
0

Severity breakdown

  • High 3
  • Medium 1

Disclosures per year

  1. 2020: 3
  2. 2021: 0
  3. 2022: 0
  4. 2023: 0
  5. 2024: 0
  6. 2025: 0
  7. 2026: 1
  1. plone.app.dexterity has a Denial of Service due to excessive title or description length this entry
    Medium · 6.5 CVE-2026-57576 >= 5.0.0, < 5.0.1, >= 4.0.0, < 4.1.3, < 3.2.3 5.0.1, 4.1.3, 3.2.3
  2. High · 8.8 CVE-2020-28736 < 2.6.8 2.6.8
  3. High · 8.8 CVE-2020-28735 < 2.6.8 2.6.8
  4. High · 8.8 CVE-2020-28734 < 2.6.8 2.6.8

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