high8.2
CVE-2026-54736
Phalcon: Non-constant-time HMAC verification in `Encryption\Crypt::decrypt` (timing side-channel)
Impact
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 packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| composer | phalcon/cphalcon | <= 5.14.0 | 5.14.1 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-8jqh-95g6-7jpj
- https://github.com/phalcon/cphalcon/security/advisories/GHSA-8jqh-95g6-7jpj
- https://nvd.nist.gov/vuln/detail/CVE-2026-54736
- https://github.com/phalcon/cphalcon/issues/17090
- https://github.com/phalcon/cphalcon/pull/17091
- https://github.com/phalcon/cphalcon/commit/ad53ab1b2e7ec59b3af92b0b37b8aaa099011137
- https://github.com/phalcon/cphalcon/releases/tag/v5.14.1