{
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"cveMetadata": {
"cveId": "CVE-2026-6104",
"assignerOrgId": "dd77f84a-d19a-4638-8c3d-a322d820ed2b",
"state": "PUBLISHED",
"assignerShortName": "php",
"dateReserved": "2026-04-11T04:15:03.938Z",
"datePublished": "2026-05-10T04:35:17.328Z",
"dateUpdated": "2026-07-15T00:41:42.455Z"
},
"containers": {
"cna": {
"providerMetadata": {
"orgId": "dd77f84a-d19a-4638-8c3d-a322d820ed2b",
"shortName": "php",
"dateUpdated": "2026-05-10T04:35:17.328Z"
},
"title": "Global buffer over-read in mb_convert_encoding() with attacker-supplied encoding",
"datePublic": "2026-05-07T00:00:00.000Z",
"problemTypes": [
{
"descriptions": [
{
"lang": "en",
"cweId": "CWE-125",
"description": "CWE-125 Out-of-bounds Read",
"type": "CWE"
}
]
}
],
"affected": [
{
"vendor": "PHP Group",
"product": "PHP",
"packageName": "mbstring",
"versions": [
{
"status": "affected",
"version": "8.4.*",
"lessThan": "8.4.21",
"versionType": "semver"
},
{
"status": "affected",
"version": "8.5.*",
"lessThan": "8.5.6",
"versionType": "semver"
}
],
"defaultStatus": "unaffected"
}
],
"descriptions": [
{
"lang": "en",
"value": "In PHP versions 8.4.* before 8.4.21 and 8.5.* before 8.5.6, when an encoding name containing an embedded NUL byte is passed to mb_convert_encoding() or related mbstring functions, the code incorrectly assumes that when strncasecmp() returns 0 it means the strings have the same length. This can lead to out-of-bounds read of global memory, potentially causing a crash or information disclosure or crash. Affected functions include mb_convert_encoding(), mb_detect_encoding(), mb_convert_variables(), and mb_detect_order(), as well as the mbstring.detect_order and mbstring.http_output INI settings.",
"supportingMedia": [
{
"type": "text/html",
"base64": false,
"value": "In PHP versions 8.4.* before 8.4.21 and 8.5.* before 8.5.6, when an encoding name containing an embedded NUL byte is passed to mb_convert_encoding() or related mbstring functions, the code incorrectly assumes that when strncasecmp() returns 0 it means the strings have the same length. This can lead to out-of-bounds read of global memory, potentially causing a crash or information disclosure or crash. Affected functions include mb_convert_encoding(), mb_detect_encoding(), mb_convert_variables(), and mb_detect_order(), as well as the mbstring.detect_order and mbstring.http_output INI settings."
}
]
}
],
"references": [
{
"url": "https://github.com/php/php-src/security/advisories/GHSA-74r9-qxhc-fx53",
"tags": [
"vendor-advisory"
]
}
],
"metrics": [
{
"format": "CVSS",
"scenarios": [
{
"lang": "en",
"value": "GENERAL"
}
],
"cvssV4_0": {
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"attackRequirements": "PRESENT",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"vulnConfidentialityImpact": "LOW",
"subConfidentialityImpact": "LOW",
"vulnIntegrityImpact": "NONE",
"subIntegrityImpact": "NONE",
"vulnAvailabilityImpact": "LOW",
"subAvailabilityImpact": "LOW",
"exploitMaturity": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"valueDensity": "NOT_DEFINED",
"vulnerabilityResponseEffort": "MODERATE",
"providerUrgency": "AMBER",
"version": "4.0",
"baseSeverity": "MEDIUM",
"baseScore": 6.3,
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/SC:L/SI:N/SA:L/RE:M/U:Amber"
}
}
],
"credits": [
{
"lang": "en",
"value": "Akshay Jain",
"type": "reporter"
},
{
"lang": "en",
"value": "Ilija Tovilo",
"type": "remediation developer"
}
],
"source": {
"advisory": "GHSA-74r9-qxhc-fx53",
"discovery": "EXTERNAL"
},
"x_generator": {
"engine": "Vulnogram 0.2.0"
}
},
"adp": [
{
"metrics": [
{
"other": {
"type": "ssvc",
"content": {
"timestamp": "2026-05-11T13:04:44.572023Z",
"id": "CVE-2026-6104",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "yes"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
}
],
"title": "CISA ADP Vulnrichment",
"providerMetadata": {
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP",
"dateUpdated": "2026-05-11T13:04:58.462Z"
}
},
{
"affected": [
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux:10.2"
],
"defaultStatus": "affected",
"packageName": "php8.4",
"product": "Red Hat Enterprise Linux 10",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:8.4.21-1.el10_2",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux:10"
],
"defaultStatus": "unaffected",
"packageName": "php",
"product": "Red Hat Enterprise Linux 10",
"vendor": "Red Hat"
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux:6"
],
"defaultStatus": "unaffected",
"packageName": "php",
"product": "Red Hat Enterprise Linux 6",
"vendor": "Red Hat"
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux:7"
],
"defaultStatus": "unaffected",
"packageName": "php",
"product": "Red Hat Enterprise Linux 7",
"vendor": "Red Hat"
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux:8"
],
"defaultStatus": "unaffected",
"packageName": "php:7.4/php",
"product": "Red Hat Enterprise Linux 8",
"vendor": "Red Hat"
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux:8"
],
"defaultStatus": "unaffected",
"packageName": "php:8.2/php",
"product": "Red Hat Enterprise Linux 8",
"vendor": "Red Hat"
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux:9"
],
"defaultStatus": "unaffected",
"packageName": "php",
"product": "Red Hat Enterprise Linux 9",
"vendor": "Red Hat"
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux:9"
],
"defaultStatus": "unaffected",
"packageName": "php:8.2/php",
"product": "Red Hat Enterprise Linux 9",
"vendor": "Red Hat"
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux:9"
],
"defaultStatus": "unaffected",
"packageName": "php:8.3/php",
"product": "Red Hat Enterprise Linux 9",
"vendor": "Red Hat"
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:hummingbird:1"
],
"defaultStatus": "unaffected",
"packageName": "php",
"product": "Red Hat Hardened Images",
"vendor": "Red Hat"
}
],
"datePublic": "2026-05-10T04:35:17.328Z",
"descriptions": [
{
"lang": "en",
"value": "A flaw was found in PHP. When an encoding name containing an embedded NUL byte is passed to `mb_convert_encoding()` or related mbstring functions, an out-of-bounds read of only 1 byte can occur due to the incorrect processing of string lengths. This issue can cause a denial of service or limited information disclosure."
}
],
"metrics": [
{
"other": {
"content": {
"namespace": "https://access.redhat.com/security/updates/classification/",
"value": "Important"
},
"type": "Red Hat severity rating"
}
},
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 8.2,
"baseSeverity": "HIGH",
"confidentialityImpact": "LOW",
"integrityImpact": "NONE",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H",
"version": "3.1"
},
"format": "CVSS"
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-125",
"description": "Out-of-bounds Read",
"lang": "en",
"type": "CWE"
}
]
}
],
"references": [
{
"tags": [
"vdb-entry",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/security/cve/CVE-2026-6104"
},
{
"name": "RHBZ#2468573",
"tags": [
"issue-tracking",
"x_refsource_REDHAT"
],
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2468573"
},
{
"tags": [
"x_sadp-csaf-vex"
],
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-6104.json"
},
{
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:22649"
}
],
"solutions": [
{
"lang": "en",
"value": "RHSA-2026:22649: Red Hat Enterprise Linux AppStream (v. 10)"
}
],
"timeline": [
{
"lang": "en",
"time": "2026-05-10T06:01:02.802Z",
"value": "Reported to Red Hat."
},
{
"lang": "en",
"time": "2026-05-10T04:35:17.328Z",
"value": "Made public."
}
],
"title": "php: global buffer over-read in mb_convert_encoding() with attacker-supplied encoding",
"workarounds": [
{
"lang": "en",
"value": "To mitigate this vulnerability, sanitize any input containing a NUL byte before calling the vulnerable mbstring functions. Also, verify your PHP configuration to ensure the vulnerable INI settings are using securely hardcoded encodings."
}
],
"x_adpType": "supplier",
"x_generator": {
"engine": "sadp-cli 1.0.0"
},
"providerMetadata": {
"orgId": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
"shortName": "redhat-SADP",
"dateUpdated": "2026-07-15T00:41:42.455Z"
}
}
]
}
}