ubuntu-cve-2026-52761
Vulnerability from osv_ubuntu
Published
2026-07-13 00:00
Modified
2026-07-13 00:00
Summary
Details

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
N/A (UNKNOWN)
medium
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libmodsecurity3",
            "binary_version": "3.0.4-1build1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "modsecurity",
        "purl": "pkg:deb/ubuntu/modsecurity@3.0.4-1build1?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.0.3-1",
        "3.0.4-1",
        "3.0.4-1build1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libmodsecurity3",
            "binary_version": "3.0.6-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "modsecurity",
        "purl": "pkg:deb/ubuntu/modsecurity@3.0.6-1?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.0.4-2",
        "3.0.6-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libmodsecurity3t64",
            "binary_version": "3.0.12-1.1build2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "modsecurity",
        "purl": "pkg:deb/ubuntu/modsecurity@3.0.12-1.1build2?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.0.10-1",
        "3.0.11-1",
        "3.0.12-1",
        "3.0.12-1.1build1",
        "3.0.12-1.1build2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libmodsecurity3t64",
            "binary_version": "3.0.14-1build2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "modsecurity",
        "purl": "pkg:deb/ubuntu/modsecurity@3.0.14-1build2?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.0.14-1build1",
        "3.0.14-1build2"
      ]
    }
  ],
  "aliases": [],
  "details": "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.",
  "id": "UBUNTU-CVE-2026-52761",
  "modified": "2026-07-13T00:00:00Z",
  "published": "2026-07-13T00:00:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-52761"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-52761"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/owasp-modsecurity/ModSecurity/security/advisories/GHSA-qjgm-7gp4-f8qq"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/owasp-modsecurity/ModSecurity/commit/edcd010814e234d46e2ec55a0f1078ff9d3032e4"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/owasp-modsecurity/ModSecurity/releases/tag/v3.0.16"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-52761"
  ]
}



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