Vulnerability from bitnami_vulndb
Published
2026-05-12 08:55
Modified
2026-09-10 15:46
Summary
Global buffer over-read in mb_convert_encoding() with attacker-supplied encoding
Details

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.

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{
  "affected": [
    {
      "package": {
        "ecosystem": "Bitnami",
        "name": "php",
        "purl": "pkg:bitnami/php"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "8.4.0"
            },
            {
              "fixed": "8.4.21"
            },
            {
              "introduced": "8.5.0"
            },
            {
              "fixed": "8.5.6"
            }
          ],
          "type": "SEMVER"
        }
      ],
      "severity": [
        {
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H",
          "type": "CVSS_V3"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-6104"
  ],
  "database_specific": {
    "cpes": [
      "cpe:2.3:a:php:php:*:*:*:*:*:*:*:*"
    ],
    "severity": "Critical"
  },
  "details": "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\u00a0strncasecmp()\u00a0returns 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.\u00a0Affected 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.",
  "id": "BIT-php-2026-6104",
  "modified": "2026-09-10T15:46:03.895Z",
  "published": "2026-05-12T08:55:59.545Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/php/php-src/security/advisories/GHSA-74r9-qxhc-fx53"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-6104"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:22649"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2026-6104"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2468573"
    },
    {
      "type": "WEB",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-6104.json"
    }
  ],
  "schema_version": "1.6.2",
  "summary": "Global buffer over-read in mb_convert_encoding() with attacker-supplied encoding"
}



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