cve-2026-55639

{
  "document": {
    "category": "csaf_vex",
    "csaf_version": "2.0",
    "distribution": {
      "text": "Copyright © Red Hat, Inc. All rights reserved.",
      "tlp": {
        "label": "WHITE",
        "url": "https://www.first.org/tlp/"
      }
    },
    "lang": "en",
    "notes": [
      {
        "category": "legal_disclaimer",
        "text": "This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original.",
        "title": "Terms of Use"
      }
    ],
    "publisher": {
      "category": "vendor",
      "contact_details": "https://access.redhat.com/security/team/contact/",
      "issuing_authority": "Red Hat Product Security is responsible for vulnerability handling across all Red Hat products and services.",
      "name": "Red Hat Product Security",
      "namespace": "https://www.redhat.com"
    },
    "references": [
      {
        "category": "self",
        "summary": "Canonical URL",
        "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-55639.json"
      }
    ],
    "title": "xrdp: improper input validation in MCS data processing leads to potential information leak",
    "tracking": {
      "current_release_date": "2026-07-21T20:54:29+00:00",
      "generator": {
        "date": "2026-07-21T20:54:29+00:00",
        "engine": {
          "name": "Red Hat SDEngine",
          "version": "5.3.7"
        }
      },
      "id": "CVE-2026-55639",
      "initial_release_date": "2026-07-20T17:14:50.233000+00:00",
      "revision_history": [
        {
          "date": "2026-07-20T17:14:50.233000+00:00",
          "number": "1",
          "summary": "Initial version"
        },
        {
          "date": "2026-07-20T21:34:28.958169+00:00",
          "number": "2",
          "summary": "Current version"
        },
        {
          "date": "2026-07-21T20:54:29+00:00",
          "number": "3",
          "summary": "Last generated version"
        }
      ],
      "status": "final",
      "version": "3"
    }
  },
  "product_tree": {
    "branches": [
      {
        "category": "vendor",
        "name": "Red Hat",
        "product": {
          "name": "All currently supported Red Hat products",
          "product_id": "red_hat_products",
          "product_identification_helper": {
            "cpe": "cpe:/a:redhat"
          }
        }
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2026-55639",
      "discovery_date": "2026-07-20T18:01:40.641035+00:00",
      "flags": [
        {
          "label": "vulnerable_code_not_present",
          "product_ids": [
            "red_hat_products"
          ]
        }
      ],
      "notes": [
        {
          "category": "description",
          "text": "xrdp is an open source RDP server. Versions 0.10.6 and prior contain a vulnerability concerning the parsing of Client Security Data within the Client MCS Connect Initial PDU with GCC Conference Create Request during the connection sequence. During the initial capability and security negotiation phase, the parser fails to perform sufficient length validation for the incoming data block. A remote, unauthenticated attacker could potentially exploit this flaw by sending a specially crafted RDP packet containing malformed data. Due to missing bounds checks, the xrdp process may read a small number of bytes beyond the declared data block boundary, potentially disclosing process memory contents that could be combined with other vulnerabilities. This issue has been fixed in version 0.10.6.1.",
          "title": "Vulnerability description"
        },
        {
          "category": "other",
          "text": "Red Hat Product Security has determined that this vulnerability does not affect any currently supported Red Hat product. This assessment may evolve based on further analysis and discovery. For more information about this vulnerability and the products it affects, please see the linked references.",
          "title": "Statement"
        },
        {
          "category": "general",
          "text": "The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.",
          "title": "CVSS score applicability"
        }
      ],
      "product_status": {
        "known_not_affected": [
          "red_hat_products"
        ]
      },
      "references": [
        {
          "category": "self",
          "summary": "Canonical URL",
          "url": "https://access.redhat.com/security/cve/CVE-2026-55639"
        },
        {
          "category": "external",
          "summary": "https://www.cve.org/CVERecord?id=CVE-2026-55639",
          "url": "https://www.cve.org/CVERecord?id=CVE-2026-55639"
        }
      ],
      "release_date": "2026-07-20T17:14:50.233000+00:00",
      "scores": [
        {
          "cvss_v3": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 5.3,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
            "version": "3.1"
          },
          "products": [
            "red_hat_products"
          ]
        }
      ],
      "title": "xrdp: improper input validation in MCS data processing leads to potential information leak"
    }
  ]
}