CVE-2026-55590
CVE-2026-55590 is a Open Redirect vulnerability in cakephp/authentication. O3 Security confirms whether CVE-2026-55590 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
CakePHP: Open redirect weakness via backslash bypass
Blast Radius
cakephp/authentication🐘cakephp/authenticationReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
CakePHP Authentication is an authentication plugin for CakePHP that can also be used in PSR-7 based applications. Prior to 2.11.1, 3.3.6, and 4.1.1, the getLoginRedirect() method contains a weakness to backslash bypasses that allows redirect targets with attacker-controlled hostnames through the redirect query string parameter. This issue is fixed in versions 2.11.1, 3.3.6, and 4.1.1.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | cakephp/authentication | all versions | 3.3.6 |
| 🐘Packagist | cakephp/authentication | ≥ 4.0.0&&< 4.1.1 | 4.1.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for cakephp/authentication. 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 cakephp/authentication to 3.3.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-55590 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-2026-55590 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-2026-55590. 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-2026-55590 in your dependencies?
O3 detects CVE-2026-55590 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.