CVE-2026-52761 (GCVE-0-2026-52761)

Vulnerability from cvelistv5 – Published: 2026-07-10 21:40 – Updated: 2026-07-10 21:40
VLAI
Title
ModSecurity: Transformation utf8toUnicode produces wrong output on i386 architecture
Summary
ModSecurity is an open source, cross platform web application firewall (WAF) engine for Apache, IIS and Nginx. From 3.0.0 through 3.0.15, the t:utf8toUnicode transformation in src/actions/transformations/utf8_to_unicode.cc produces wrong output on i386 architecture because snprintf uses sizeof on a char pointer rather than the length of the unicode buffer, allowing rules that use this transformation to be bypassed on i386 architecture. This issue is fixed in version 3.0.16.
Severity
5.8 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
CWE
  • CWE-467 - Use of sizeof() on a Pointer Type
Assigner
References
Impacted products
Vendor Product Version
owasp-modsecurity ModSecurity Affected: >= 3.0.0, < 3.0.16
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        }
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            "confidentialityImpact": "NONE",
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            "privilegesRequired": "NONE",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-467",
              "description": "CWE-467: Use of sizeof() on a Pointer Type",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-07-10T21:40:23.961Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
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          "name": "https://github.com/owasp-modsecurity/ModSecurity/security/advisories/GHSA-qjgm-7gp4-f8qq",
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          "url": "https://github.com/owasp-modsecurity/ModSecurity/security/advisories/GHSA-qjgm-7gp4-f8qq"
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        },
        {
          "name": "https://github.com/owasp-modsecurity/ModSecurity/releases/tag/v3.0.16",
          "tags": [
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          "url": "https://github.com/owasp-modsecurity/ModSecurity/releases/tag/v3.0.16"
        }
      ],
      "source": {
        "advisory": "GHSA-qjgm-7gp4-f8qq",
        "discovery": "UNKNOWN"
      },
      "title": "ModSecurity: Transformation utf8toUnicode produces wrong output on i386 architecture"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-52761",
    "datePublished": "2026-07-10T21:40:23.961Z",
    "dateReserved": "2026-06-08T17:13:43.063Z",
    "dateUpdated": "2026-07-10T21:40:23.961Z",
    "state": "PUBLISHED"
  },
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  "vulnerability-lookup:meta": {
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      "date": "2026-07-12",
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    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-07-11T07:34:59+00:00",
      "cve": "CVE-2026-52761",
      "id": "CVE-2026-52761",
      "initial_release_date": "2026-07-10T21:40:23.961000+00:00",
      "product_status:known_affected": "8",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "ModSecurity: ModSecurity: Web Application Firewall rules bypass due to incorrect UTF-8 to Unicode transformation",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-52761.json",
      "version": "3"
    }
  }
}



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