CVE-2026-54736: Phalcon Cphalcon

High severity, CVSS 8.2. EPSS: 0.2% chance of exploitation in the next 30 days.

Phalcon is a high-performance, full-stack PHP framework. Prior to 5.14.1, Phalcon\Encryption\Crypt::decrypt compares the attacker-supplied HMAC tag against the freshly computed HMAC using PHP/Zephir identity comparison, which lowers to a byte-wise comparison that returns early on the first differing byte. This observable timing discrepancy can allow an attacker to recover a valid tag byte-by-byte and attach it to a chosen IV and ciphertext so that decrypt() accepts tampered encrypted content as authentic. This issue is fixed in version 5.14.1.

Affected products

• Phalcon Cphalcon: before 5.14.1 (fixed in 5.14.1)

Published 2026-07-10. Last modified 2026-07-13.