CVE-2026-57584: Phalcon: Catastrophic backtracking (ReDoS) in the default Phalcon Router route lead to remote unauthenticated DoS
Phalcon is a high-performance, full-stack PHP framework. Prior to 5.15.0, every Phalcon MVC application built with a default router registers a built-in route whose compiled PCRE pattern contains the nested quantifier (/.), and the same construct is produced by the /:params placeholder and the CLI router. Phalcon\Mvc\Router::handle() matches this pattern against the attacker-controlled request URI on every request, so a crafted path such as one containing repeated slashes followed by decoded newlines can trigger catastrophic backtracking and cause CPU exhaustion or route-matching failure. This issue is fixed in version 5.15.0.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Phalconto a version that resolves this vulnerability.Fixed in 5.15.0
Event History
Frequently Asked Questions
What is the severity of CVE-2026-57584?
CVE-2026-57584 has a severity rating of high with a CVSS score of 8.7.
What type of attack does CVE-2026-57584 enable?
CVE-2026-57584 allows for remote unauthenticated denial of service (DoS) due to catastrophic backtracking in the default Phalcon Router.
How can I mitigate CVE-2026-57584?
To mitigate CVE-2026-57584, upgrade to Phalcon PHP Framework version 5.15.0 or later.
Which framework is affected by CVE-2026-57584?
CVE-2026-57584 affects the Phalcon PHP Framework prior to version 5.15.0.
What does CVE-2026-57584 exploit in the Phalcon Router?
CVE-2026-57584 exploits a built-in route with a compiled PCRE pattern that includes a nested quantifier.