CVE-2026-28413
MEDIUMProducts.isurlinportal: Possible open redirect when using more than 2 forward slashes
EPSS Exploitation Probability
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.
Blast Radius
products-isurlinportal🐍products-isurlinportal🐍products-isurlinportal🐍products-isurlinportal🐍products-isurlinportalReal-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
Products.isurlinportal is a replacement for isURLInPortal method in Plone. Prior to versions 2.1.0, 3.1.0, and 4.0.0, a url /login?came_from=////evil.example may redirect to an external website after login. This issue has been patched in versions 2.1.0, 3.1.0, and 4.0.0.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | products-isurlinportal | ≥ 4.0.0a1&&< 4.0.0 | 4.0.0 |
| 🐍PyPI | products-isurlinportal | ≥ 3.0.0&&< 3.1.0 | 3.1.0 |
| 🐍PyPI | products-isurlinportal | all versions | 2.1.0 |
| 🐍PyPI | products-isurlinportal | all versions | 2.1.0 |
| 🐍PyPI | products-isurlinportal | ≥ 3.0.0&&< 3.1.0 | 3.1.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for products-isurlinportal. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update products-isurlinportal to 4.0.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-28413 is resolved across your whole dependency graph.
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.
How O3 protects you
O3 pinpoints whether CVE-2026-28413 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-28413. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-28413 in your dependencies?
O3 detects CVE-2026-28413 across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.