CVE-2026-54736

HIGH

Phalcon: Non-constant-time HMAC verification in `Encryption\Crypt::decrypt` (timing side-channel)

Title source: cna
STIX 2.1

Description

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.

References (5)

Core 5

Scores

CVSS v4 8.2
EPSS 0.0015
EPSS Percentile 4.5%
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-208 CWE-347
Status published
Products (1)
phalcon/cphalcon < 5.14.1
Published Jul 10, 2026
Tracked Since Jul 11, 2026