FKIE_CVE-2025-66490

Vulnerability from fkie_nvd - Published: 2025-12-09 01:16 - Updated: 2026-10-14 22:10
Severity
6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Summary
Traefik is an HTTP reverse proxy and load balancer. For versions prior to 2.11.32 and 2.11.31 through 3.6.2, requests using PathPrefix, Path or PathRegex matchers can bypass path normalization. When Traefik uses path-based routing, requests containing URL-encoded restricted characters (/, \, Null, ;, ?, #) can bypass the middleware chain and reach unintended backends. For example, a request to http://mydomain.example.com/admin%2F could reach service-a without triggering my-security-middleware, bypassing security controls for the /admin/ path. This issue is fixed in versions 2.11.32 and 3.6.3.
References
security-advisories@github.comhttps://github.com/traefik/traefik/releases/tag/v2.11.32Release Notes
security-advisories@github.comhttps://github.com/traefik/traefik/releases/tag/v3.6.4Release Notes
security-advisories@github.comhttps://github.com/traefik/traefik/security/advisories/GHSA-gm3x-23wp-hc2cExploit, Vendor Advisory
134c704f-9b21-4f2e-91b3-4a467353bcc0https://github.com/traefik/traefik/security/advisories/GHSA-gm3x-23wp-hc2cExploit, Vendor Advisory
Impacted products
Vendor Product Version
traefik traefik *
traefik traefik *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "traefik",
          "vendor": "traefik",
          "versions": [
            {
              "status": "affected",
              "version": "github.com/traefik/traefik/v3  \u003c 3.6.3"
            },
            {
              "status": "affected",
              "version": "github.com/traefik/traefik/v2 \u003c 2.11.32"
            },
            {
              "status": "affected",
              "version": "github.com/traefik/traefik \u003c= 1.7.34"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "A212D168-0836-4D72-B2D9-9209C299471D",
              "versionEndExcluding": "2.11.32",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "0ED22672-D0CC-47CC-A70A-E270FDA55FBC",
              "versionEndExcluding": "3.6.3",
              "versionStartIncluding": "3.0.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Traefik is an HTTP reverse proxy and load balancer. For versions prior to 2.11.32 and 2.11.31 through 3.6.2, requests using PathPrefix, Path or PathRegex matchers can bypass path normalization. When Traefik uses path-based routing, requests containing URL-encoded restricted characters (/, \\, Null, ;, ?, #) can bypass the middleware chain and reach unintended backends. For example, a request to http://mydomain.example.com/admin%2F could reach service-a without triggering my-security-middleware, bypassing security controls for the /admin/ path. This issue is fixed in versions 2.11.32 and 3.6.3."
    },
    {
      "lang": "es",
      "value": "Traefik es un proxy inverso HTTP y balanceador de carga. Para versiones anteriores a 2.11.32 y 2.11.31 hasta 3.6.2, las solicitudes que utilizan los emparejadores PathPrefix, Path o PathRegex pueden eludir la normalizaci\u00f3n de rutas. Cuando Traefik utiliza enrutamiento basado en rutas, las solicitudes que contienen caracteres restringidos codificados en URL (/, \\, Null, ;, ?, #) pueden eludir la cadena de middleware y alcanzar backends no deseados. Por ejemplo, una solicitud a http://mydomain.example.com/admin%2F podr\u00eda llegar a service-a sin activar my-security-middleware, eludiendo los controles de seguridad para la ruta /admin/. Este problema est\u00e1 solucionado en las versiones 2.11.32 y 3.6.3."
    }
  ],
  "id": "CVE-2025-66490",
  "lastModified": "2026-10-14T22:10:00.210",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 2.5,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ],
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 6.9,
          "baseSeverity": "MEDIUM",
          "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": "LOW",
          "subIntegrityImpact": "LOW",
          "userInteraction": "NONE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/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": "NONE",
          "vulnConfidentialityImpact": "NONE",
          "vulnIntegrityImpact": "NONE",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2025-66490",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2025-12-09T14:17:38.617610Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2025-12-09T01:16:55.540",
  "references": [
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Release Notes"
      ],
      "url": "https://github.com/traefik/traefik/releases/tag/v2.11.32"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Release Notes"
      ],
      "url": "https://github.com/traefik/traefik/releases/tag/v3.6.4"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ],
      "url": "https://github.com/traefik/traefik/security/advisories/GHSA-gm3x-23wp-hc2c"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ],
      "url": "https://github.com/traefik/traefik/security/advisories/GHSA-gm3x-23wp-hc2c"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-436"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    },
    {
      "description": [
        {
          "lang": "en",
          "value": "NVD-CWE-noinfo"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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