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Not in CISA KEV
HIGH severity

CVE-2013-4200 — plone

HIGH

CVE-2013-4200 is a high-severity (CVSS 7.5) vulnerability in plone. 1 public exploit reference exists, so weaponization risk is real. A fix is available for plone — see the affected versions and patch details below.

Plone Open Redirection vulnerability via next parameter

Also known asPYSEC-2014-64
Published
May 14, 2022
Updated
Oct 15, 2024
Affected
3 pkgs
Patched
3 / 3
Exploits
1 known
Exploitation data as of Sep 24, 2026 · OSV.dev, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗
2.2%probability of exploitation in next 30 days
Lower Risk0.00%
Lower risk than most CVEs82th percentile — riskier than 82% of all scored CVEsHighest risk

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

How urgent is this, really

CVE-2013-4200 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.

Where this sits among everything scored

Of 378,567 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.

Real-World Exposure

3 pkgs affected
🐍plone🐍plone🐍plone

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.

Description

The isURLInPortal method in the URLTool class in in_portal.py in Plone 2.1 through 4.1, 4.2.x through 4.2.5, and 4.3.x through 4.3.1 treats URLs starting with a space as a relative URL, which allows remote attackers to bypass the allow_external_login_sites filtering property, redirect users to arbitrary web sites, and conduct phishing attacks via a space before a URL in the "next" parameter to acl_users/credentials_cookie_auth/require_login.

Affected Packages

3 total 3 fixed
EcosystemPackageVulnerable rangeFix
🐍PyPIplone≥ 2.1&&< 4.1.14.1.1pip install --upgrade 'plone==4.1.1'
🐍PyPIplone≥ 4.2&&< 4.2.64.2.6pip install --upgrade 'plone==4.2.6'
🐍PyPIplone≥ 4.3&&< 4.3.24.3.2pip install --upgrade 'plone==4.3.2'
Exploits & PoCs
1

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

EDB-38738webappspython✓ Verified

Plone - 'in_portal.py' < 4.1.3 Session Hijacking

by Cyrill Bannwart · Jul 31, 2013

Detection & mitigation playbook

Open-source dependency
  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for plone, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

  2. Fix

    Update plone to 4.1.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2013-4200 is resolved across your whole dependency graph.

  3. Workarounds

    If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

  4. How O3 protects you

    O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2013-4200 can be triaged on real exposure rather than presence alone.

Tailored to CVE-2013-4200. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

The isURLInPortal method in the URLTool class in in_portal.py in Plone 2.1 through 4.1, 4.2.x through 4.2.5, and 4.3.x through 4.3.1 treats URLs starting with a space as a relative URL, which allows remote attackers to bypass the allow_external_login_sites filtering property, redirect users to arbitrary web sites, and conduct phishing attacks via a space before a URL in the "next" parameter to acl_users/credentials_cookie_auth/require_login.
O3 Security · Impact-Aware SCA

Is CVE-2013-4200 in your dependencies?

O3 Security finds CVE-2013-4200 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.

CVE-2013-4200: plone (High 7.5) | O3 Security