High
Phalcon: Non-constant-time HMAC verification in `Encryption\Crypt::decrypt` (timing side-channel)
Type: advisorySources: OSV
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.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-54736
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 4 Nov 2026, 17:44 UTC · Revision 1
Source evidence
Phalcon: Non-constant-time HMAC verification in `Encryption\Crypt::decrypt` (timing side-channel)
core-osv · Original sourcePublished 10 Jul 2026, 21:02 UTC
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.
osv:CVE-2026-54736
Complete source record
{
"id": "a6e55a683a9d0a88f0e5fea8c73449f84052c8b6ceba140ac5a9ee4b4f224131",
"url": "https://osv.dev/vulnerability/CVE-2026-54736",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "Phalcon: Non-constant-time HMAC verification in `Encryption\\Crypt::decrypt` (timing side-channel)",
"summary": "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.",
"evidence": "osv:CVE-2026-54736",
"products": [],
"severity": "high",
"structured": {
"id": "CVE-2026-54736",
"aliases": [
"CVE-2026-54736",
"GHSA-8jqh-95g6-7jpj"
],
"metrics": [
{
"type": "CVSS_V4",
"score": "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"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/phalcon/cphalcon",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "4e4bb3756654c3ee3e8ac6f7ee2be0705edb2fdf"
},
{
"fixed": "ad53ab1b2e7ec59b3af92b0b37b8aaa099011137"
}
],
"database_specific": {
"extracted_events": [
{
"range": [
{
"introduced": "0"
},
{
"fixed": "5.14.1"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StringRangeExpression"
},
{
"range": [
{
"fixed": "ad53ab1b2e7ec59b3af92b0b37b8aaa099011137"
}
],
"source": "REFERENCES_COMMIT"
},
{
"range": [
{
"fixed": "4e4bb3756654c3ee3e8ac6f7ee2be0705edb2fdf"
}
],
"source": "REFERENCES_TAG",
"original_tag": "v5.14.1"
}
]
}
}
],
"versions": [
"v5.14.0",
"v5.13.0",
"v5.12.1",
"5.12.0",
"v5.11.1",
"v5.11.0",
"v5.10.0",
"v5.9.3",
"v5.9.2",
"v5.9.1",
"v5.9.0",
"v5.8.0",
"v5.7.0",
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"v5.6.1",
"v5.6.0",
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"v5.0.0RC3",
"v5.0.0RC2",
"v5.0.0RC1",
"v5.0.0beta3",
"v5.0.0beta2",
"v5.0.0beta1",
"v5.0.0alpha7",
"v5.0.0alpha6",
"v5.0.0alpha5",
"v5.0.0alpha4",
"v5.0.0alpha3",
"5.0.0alpha3",
"v5.0.0-alpha.2",
"v5.0.0-alpha.1",
"v4.1.0",
"v4.0.6",
"v4.0.5",
"v4.0.4",
"v4.0.3",
"v4.0.2",
"v4.0.1",
"v4.0.0",
"v4.0.0-rc.3",
"v4.0.0-rc.2",
"v4.0.0-rc.1",
"v4.0.0-beta.2",
"v4.0.0-beta.1",
"v4.0.0-alpha.5",
"v4.0.0-alpha.3",
"v4.0.0-alpha.2",
"v3.2.2",
"v3.2.1",
"v3.2.0",
"v3.1.2",
"v3.1.1",
"v3.1.0",
"v3.0.4",
"v3.0.3",
"v3.0.2",
"v3.0.1",
"v3.0.0",
"phalcon-v2.0.13",
"phalcon-v2.0.11",
"phalcon-v2.0.10",
"phalcon-v2.0.9",
"phalcon-v2.0.8",
"phalcon-v2.0.7",
"phalcon-v2.0.6",
"phalcon-v2.0.5",
"phalcon-v2.0.4",
"phalcon-v2.0.3",
"phalcon-v2.0.2",
"phalcon-v2.0.1",
"phalcon-v2.0.0",
"phalcon-v1.3.4",
"phalcon-v1.3.3",
"phalcon-v1.3.2",
"phalcon-v1.3.1",
"phalcon-v1.3.0",
"v1.2.0",
"phalcon-v1.2.0",
"v1.1.0",
"phalcon-v1.1.0",
"v1.0.1",
"phalcon-v1.0.1",
"v1.0.0",
"phalcon-v1.0.0",
"v0.9.0",
"phalcon-v0.9.0",
"v0.7.0",
"phalcon-v0.7.0"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-54736.json"
}
}
],
"modified": "2026-10-28T02:30:38.049191415Z",
"provider": "osv",
"references": [
"https://github.com/phalcon/cphalcon/releases/tag/v5.14.1",
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54736.json",
"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/commit/ad53ab1b2e7ec59b3af92b0b37b8aaa099011137",
"https://github.com/phalcon/cphalcon/pull/17091"
],
"provider_metadata": {
"cwe_ids": [
"CWE-208",
"CWE-347"
],
"cna_assigner": "GitHub_M",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54736.json"
}
},
"related_cves": [
{
"value": "CVE-2026-54736",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 505438,
"published_at": "2026-07-10T21:02:53.873+00:00"
}