CVE-2026-59851

{
  "id": "CVE-2026-59851",
  "sourceIdentifier": "[email protected]",
  "published": "2026-07-21T15:16:37.897",
  "lastModified": "2026-11-04T23:17:54.300",
  "vulnStatus": "Undergoing Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A flaw was found in libssh. On servers with GSSAPIKeyExchange enabled, the gssapi-keyex path does not verify whether the authenticated Kerberos principal is authorized for the requested local user, allowing authenticated clients to log in as arbitrary users."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 10",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libssh",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:10.2"
          ],
          "versions": [
            {
              "version": "0:0.12.0-3.el10_2",
              "lessThan": "*",
              "versionType": "rpm",
              "status": "unaffected"
            }
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Hardened Images",
          "defaultStatus": "affected",
          "collectionURL": "https://catalog.redhat.com/software/containers/",
          "packageName": "libssh-main",
          "cpes": [
            "cpe:/a:redhat:hummingbird:1"
          ],
          "versions": [
            {
              "version": "0.12.1-4.hum1",
              "lessThan": "*",
              "versionType": "rpm",
              "status": "unaffected"
            }
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 8",
          "defaultStatus": "unaffected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libssh",
          "cpes": [
            "cpe:/a:redhat:enterprise_linux:8"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 9",
          "defaultStatus": "unaffected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libssh",
          "cpes": [
            "cpe:/a:redhat:enterprise_linux:9"
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 8.8,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 5.9
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-07-22T18:14:50.808102Z",
          "id": "CVE-2026-59851",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-863"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:libssh:libssh:-:*:*:*:*:*:*:*",
              "matchCriteriaId": "9B0EB43D-D594-43B0-AB33-5E8E1A6C8BEF"
            },
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:redhat:hardened_images:-:*:*:*:*:*:*:*",
              "matchCriteriaId": "87DEB507-5B64-47D7-9A50-3B87FD1E571F"
            },
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              "matchCriteriaId": "D65C2163-CFC2-4ABB-8F4E-CB09CEBD006C"
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          ]
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  ],
  "references": [
    {
      "url": "https://access.redhat.com/errata/RHSA-2026:42922",
      "source": "[email protected]",
      "tags": [
        "Issue Tracking"
      ]
    },
    {
      "url": "https://access.redhat.com/errata/RHSA-2026:55855",
      "source": "[email protected]"
    },
    {
      "url": "https://access.redhat.com/security/cve/CVE-2026-59851",
      "source": "[email protected]",
      "tags": [
        "Vendor Advisory"
      ]
    },
    {
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2498184",
      "source": "[email protected]",
      "tags": [
        "Issue Tracking",
        "Vendor Advisory"
      ]
    }
  ]
}