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FKIE_CVE-2026-85089

Vulnerability from fkie_nvd - Published: 2026-09-03 13:06 - Updated: 2026-09-03 14:17
Severity
6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Summary
FreeRDP versions 3.0.0 through 3.30.0 (before 3.31.0) transmit uninitialized heap memory in Save Session Info PDU reserved padding fields. Three PDU writers in libfreerdp/core/info.c (rdp_write_logon_info_v2, rdp_write_logon_info_plain, and rdp_write_logon_info_ex) use Stream_Seek instead of Stream_Zero for reserved pad bytes (up to 576 bytes), leaving previously freed heap contents in the outgoing PDU. Because the send buffer is allocated with malloc (not zeroed), stale heap data — which may include cleartext credentials from prior sessions — can be sent to the receiving peer. FreeRDP-based servers using rdpUpdate::SaveSessionInfo and freerdp-proxy (which forwards these PDUs) are affected, allowing disclosure of server/proxy process memory to a downstream client.
References
disclosure@vulncheck.comhttps://github.com/FreeRDP/FreeRDP
disclosure@vulncheck.comhttps://github.com/FreeRDP/FreeRDP/blob/3.30.0/libfreerdp/core/info.c#L1541
disclosure@vulncheck.comhttps://github.com/FreeRDP/FreeRDP/commit/056cede398d71c1f2540baebc26ec3327a249301
disclosure@vulncheck.comhttps://github.com/FreeRDP/FreeRDP/commit/483c9388119f06bac420d92053cff9ef94e83bea
disclosure@vulncheck.comhttps://github.com/FreeRDP/FreeRDP/releases/tag/3.31.0
disclosure@vulncheck.comhttps://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-v649-94v2-p72q
disclosure@vulncheck.comhttps://www.vulncheck.com/advisories/freerdp-before-3.31.0-information-disclosure-via-uninitialized-heap-memory
134c704f-9b21-4f2e-91b3-4a467353bcc0https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-v649-94v2-p72q
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "FreeRDP",
          "vendor": "FreeRDP",
          "versions": [
            {
              "lessThan": "3.31.0",
              "status": "affected",
              "version": "3.0.0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "3.31.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "disclosure@vulncheck.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "FreeRDP versions 3.0.0 through 3.30.0 (before 3.31.0) transmit uninitialized heap memory in Save Session Info PDU reserved padding fields. Three PDU writers in libfreerdp/core/info.c (rdp_write_logon_info_v2, rdp_write_logon_info_plain, and rdp_write_logon_info_ex) use Stream_Seek instead of Stream_Zero for reserved pad bytes (up to 576 bytes), leaving previously freed heap contents in the outgoing PDU. Because the send buffer is allocated with malloc (not zeroed), stale heap data \u2014 which may include cleartext credentials from prior sessions \u2014 can be sent to the receiving peer. FreeRDP-based servers using rdpUpdate::SaveSessionInfo and freerdp-proxy (which forwards these PDUs) are affected, allowing disclosure of server/proxy process memory to a downstream client."
    }
  ],
  "id": "CVE-2026-85089",
  "lastModified": "2026-09-03T14:17:04.260",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 3.6,
        "source": "disclosure@vulncheck.com",
        "type": "Secondary"
      }
    ],
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 7.1,
          "baseSeverity": "HIGH",
          "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": "LOW",
          "providerUrgency": "NOT_DEFINED",
          "subAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "userInteraction": "NONE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/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": "HIGH",
          "vulnIntegrityImpact": "NONE",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "disclosure@vulncheck.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-85089",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-09-03T13:58:31.244942Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-09-03T13:06:20.277",
  "references": [
    {
      "source": "disclosure@vulncheck.com",
      "url": "https://github.com/FreeRDP/FreeRDP"
    },
    {
      "source": "disclosure@vulncheck.com",
      "url": "https://github.com/FreeRDP/FreeRDP/blob/3.30.0/libfreerdp/core/info.c#L1541"
    },
    {
      "source": "disclosure@vulncheck.com",
      "url": "https://github.com/FreeRDP/FreeRDP/commit/056cede398d71c1f2540baebc26ec3327a249301"
    },
    {
      "source": "disclosure@vulncheck.com",
      "url": "https://github.com/FreeRDP/FreeRDP/commit/483c9388119f06bac420d92053cff9ef94e83bea"
    },
    {
      "source": "disclosure@vulncheck.com",
      "url": "https://github.com/FreeRDP/FreeRDP/releases/tag/3.31.0"
    },
    {
      "source": "disclosure@vulncheck.com",
      "url": "https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-v649-94v2-p72q"
    },
    {
      "source": "disclosure@vulncheck.com",
      "url": "https://www.vulncheck.com/advisories/freerdp-before-3.31.0-information-disclosure-via-uninitialized-heap-memory"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "url": "https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-v649-94v2-p72q"
    }
  ],
  "sourceIdentifier": "disclosure@vulncheck.com",
  "vulnStatus": "Received",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-908"
        }
      ],
      "source": "disclosure@vulncheck.com",
      "type": "Secondary"
    }
  ]
}



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