FKIE_CVE-2026-18639

Vulnerability from fkie_nvd - Published: 2026-08-11 16:17 - Updated: 2026-08-28 21:17
Severity
7.3 (High) - CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N
Summary
When Velociraptor is configured to use an OIDC IdP for authentication, it uses the email claim as a username. However, some IdP allow users to change the email claim without verification. Some IdPs do not set the "email_verified" claim and do not actually verify the email. This allows a user to impersonate another user by setting their email address within the IdP, allowing account takeover.
References
cve@rapid7.comhttp://docs.velociraptor.app/announcements/advisories/cve-2026-18639/
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Velociraptor",
          "repo": "https://github.com/Velocidex/velociraptor/",
          "vendor": "Rapid7",
          "versions": [
            {
              "lessThan": "0.77.2",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "cve@rapid7.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "When Velociraptor is configured to use an OIDC IdP for authentication, it uses the email claim as a username. However, some IdP allow users to change the email claim without verification. Some IdPs do not set the \"email_verified\" claim and do not actually verify the email.\n\nThis allows a user to impersonate another user by setting their email address within the IdP, allowing account takeover."
    }
  ],
  "id": "CVE-2026-18639",
  "lastModified": "2026-08-28T21:17:10.720",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 7.3,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.1,
        "impactScore": 5.2,
        "source": "cve@rapid7.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-18639",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-08-11T17:13:54.338948Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-08-11T16:17:30.590",
  "references": [
    {
      "source": "cve@rapid7.com",
      "url": "http://docs.velociraptor.app/announcements/advisories/cve-2026-18639/"
    }
  ],
  "sourceIdentifier": "cve@rapid7.com",
  "vulnStatus": "Awaiting Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-290"
        }
      ],
      "source": "cve@rapid7.com",
      "type": "Secondary"
    }
  ]
}



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