FKIE_CVE-2026-30923

Vulnerability from fkie_nvd - Published: 2026-05-05 19:16 - Updated: 2026-07-25 11:10
Severity
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
ModSecurity is an open source, cross platform web application firewall (WAF) engine for Apache, IIS and Nginx. Libmodsecurity is one component of the ModSecurity v3 project. A segmentation fault occurs when a rule using the t:hexDecode transformation inspects a query string parameter containing a single character. An attacker can exploit this to crash worker processes, causing a denial of service. Service resumes once the attack stops as worker processes recover from the segfault. All versions before 3.0.15 of libModSecurity3 are affected. This has been patched in version 3.0.15.
References
security-advisories@github.comhttps://github.com/owasp-modsecurity/ModSecurity/releases/tag/v3.0.15Patch, Product
security-advisories@github.comhttps://github.com/owasp-modsecurity/ModSecurity/security/advisories/GHSA-qrjc-3jpc-3h2gExploit, Vendor Advisory
134c704f-9b21-4f2e-91b3-4a467353bcc0https://github.com/owasp-modsecurity/ModSecurity/security/advisories/GHSA-qrjc-3jpc-3h2gExploit, Vendor Advisory
Impacted products
Vendor Product Version
owasp modsecurity *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "ModSecurity",
          "vendor": "owasp-modsecurity",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 3.0.15"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:owasp:modsecurity:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "4A7C1264-1CA1-4F7B-879E-F449E4776302",
              "versionEndExcluding": "3.0.15",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "ModSecurity is an open source, cross platform web application firewall (WAF) engine for Apache, IIS and Nginx. Libmodsecurity is one component of the ModSecurity v3 project. A segmentation fault occurs when a rule using the t:hexDecode transformation inspects a query string parameter containing a single character. An attacker can exploit this to crash worker processes, causing a denial of service. Service resumes once the attack stops as worker processes recover from the segfault. All versions before 3.0.15 of libModSecurity3 are affected. This has been patched in version 3.0.15."
    },
    {
      "lang": "es",
      "value": "ModSecurity es un motor de cortafuegos de aplicaciones web (WAF) de c\u00f3digo abierto y multiplataforma para Apache, IIS y Nginx. Libmodsecurity es un componente del proyecto ModSecurity v3. Una falla de segmentaci\u00f3n ocurre cuando una regla que utiliza la transformaci\u00f3n t:hexDecode inspecciona un par\u00e1metro de cadena de consulta que contiene un solo car\u00e1cter. Un atacante puede explotar esto para bloquear los procesos de trabajo, causando una denegaci\u00f3n de servicio. El servicio se reanuda una vez que el ataque se detiene, ya que los procesos de trabajo se recuperan de la falla de segmentaci\u00f3n. Todas las versiones anteriores a la 3.0.15 de libModSecurity3 est\u00e1n afectadas. Esto ha sido parcheado en la versi\u00f3n 3.0.15."
    }
  ],
  "id": "CVE-2026-30923",
  "lastModified": "2026-07-25T11:10:00.100",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ],
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "PRESENT",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 8.2,
          "baseSeverity": "HIGH",
          "confidentialityRequirement": "NOT_DEFINED",
          "exploitMaturity": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "privilegesRequired": "NONE",
          "providerUrgency": "NOT_DEFINED",
          "subAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "userInteraction": "NONE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "version": "4.0",
          "vulnAvailabilityImpact": "HIGH",
          "vulnConfidentialityImpact": "NONE",
          "vulnIntegrityImpact": "NONE",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-30923",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-05-05T19:20:55.329784Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-05-05T19:16:21.567",
  "references": [
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Patch",
        "Product"
      ],
      "url": "https://github.com/owasp-modsecurity/ModSecurity/releases/tag/v3.0.15"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ],
      "url": "https://github.com/owasp-modsecurity/ModSecurity/security/advisories/GHSA-qrjc-3jpc-3h2g"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ],
      "url": "https://github.com/owasp-modsecurity/ModSecurity/security/advisories/GHSA-qrjc-3jpc-3h2g"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-125"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}



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