CVE-2026-123125

Full vulnerability record from the local CVENow database.

Description

The Symfony Validator component IpValidator incompletely classifies internal addresses in the filtered modes of the Ip constraint, so some internal addresses are accepted as public, which can lead to Server-Side Request Forgery (SSRF) in Symfony versions prior to 5.4.56, 6.x prior to 6.4.50, 7.x prior to 7.4.23, and 8.x prior to 8.1.11. In these modes, IpValidator relies on the PHP flags FILTER_FLAG_NO_PRIV_RANGE and FILTER_FLAG_NO_RES_RANGE to classify addresses as public, private, or reserved. These flags do not cover shared address space (100.64.0.0/10) or IPv4-mapped, IPv4-compatible, and 6to4 IPv6 addresses, which can embed internal IPv4 addresses. A value such as ::ffff:127.0.0.1 can therefore pass validation even though it points to an internal host. Applications that rely on the Ip constraint to reject internal addresses, for example before making a server-side request to a user-supplied address, can be exposed to SSRF.

Severity

MEDIUM

CVSS score

6.3 (v4.0)

Vulnerability status

Received

Source identifier

596c5446-0ce5-4ba2-aa66-48b3b757a647

Published

2026-11-05 16:17:46.940000

Last modified

2026-11-05 17:18:03.140000

View original CVE JSON

{
  "id": "CVE-2026-123125",
  "sourceIdentifier": "596c5446-0ce5-4ba2-aa66-48b3b757a647",
  "published": "2026-11-05T16:17:46.940",
  "lastModified": "2026-11-05T17:18:03.140",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "The Symfony Validator component IpValidator incompletely classifies internal addresses in the filtered modes of the Ip constraint, so some internal addresses are accepted as public, which can lead to Server-Side Request Forgery (SSRF) in Symfony versions prior to 5.4.56, 6.x prior to 6.4.50, 7.x prior to 7.4.23, and 8.x prior to 8.1.11.\n\nIn these modes, IpValidator relies on the PHP flags FILTER_FLAG_NO_PRIV_RANGE and FILTER_FLAG_NO_RES_RANGE to classify addresses as public, private, or reserved. These flags do not cover shared address space (100.64.0.0/10) or IPv4-mapped, IPv4-compatible, and 6to4 IPv6 addresses, which can embed internal IPv4 addresses. A value such as ::ffff:127.0.0.1 can therefore pass validation even though it points to an internal host.\nApplications that rely on the Ip constraint to reject internal addresses, for example before making a server-side request to a user-supplied address, can be exposed to SSRF."
    }
  ],
  "affected": [
    {
      "source": "596c5446-0ce5-4ba2-aa66-48b3b757a647",
      "affectedData": [
        {
          "vendor": "sensiolabs",
          "product": "symfony",
          "defaultStatus": "unaffected",
          "collectionURL": "https://packagist.org/packages/symfony/validator",
          "packageName": "symfony/validator",
          "modules": [
            "Symfony/Component/Validator/Constraints/IpValidator"
          ],
          "repo": "https://github.com/symfony/validator",
          "versions": [
            {
              "version": "0",
              "lessThan": "5.4.56",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "6.0.0",
              "lessThan": "6.4.50",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "7.0.0",
              "lessThan": "7.4.23",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "8.0.0",
              "lessThan": "8.1.11",
              "versionType": "git",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV40": [
      {
        "source": "596c5446-0ce5-4ba2-aa66-48b3b757a647",
        "type": "Secondary",
        "cvssData": {
          "version": "4.0",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/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",
          "baseScore": 6.3,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "attackRequirements": "PRESENT",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "vulnConfidentialityImpact": "NONE",
          "vulnIntegrityImpact": "NONE",
          "vulnAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "LOW",
          "subIntegrityImpact": "LOW",
          "subAvailabilityImpact": "NONE",
          "exploitMaturity": "NOT_DEFINED",
          "confidentialityRequirement": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "availabilityRequirement": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "valueDensity": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "providerUrgency": "NOT_DEFINED"
        }
      }
    ],
    "cvssMetricV31": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 2.5
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-11-05T16:58:59.042475Z",
          "id": "CVE-2026-123125",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "596c5446-0ce5-4ba2-aa66-48b3b757a647",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-184"
        },
        {
          "lang": "en",
          "value": "CWE-918"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/symfony/symfony/commit/3bf8ea37fcb402c5ecc502a3f63012df85a7572e",
      "source": "596c5446-0ce5-4ba2-aa66-48b3b757a647"
    },
    {
      "url": "https://github.com/symfony/symfony/security/advisories/GHSA-4qpf-57w4-m3wc",
      "source": "596c5446-0ce5-4ba2-aa66-48b3b757a647"
    }
  ]
}