CVE-2026-67298 (GCVE-0-2026-67298)

Vulnerability from cvelistv5 – Published: 2026-08-01 12:22 – Updated: 2026-08-01 12:22
VLAI
Title
FreeRDP 3.28.0 Heap Buffer Overflow via RAIL orderLength Underflow
Summary
FreeRDP versions 3.28.0 and earlier contain a heap buffer overflow in the server-side RAIL channel handler (rail_server_handle_messages() in channels/rail/server/rail_main.c). When processing a RAIL PDU header, the code subtracts RAIL_PDU_HEADER_LENGTH from the peer-controlled orderLength field without first verifying orderLength is at least the header length. For orderLength values 0..3 this causes an unsigned integer underflow to a very large size, which bypasses the Stream_EnsureRemainingCapacity() capacity check (due to pointer arithmetic wraparound) and is then passed to WTSVirtualChannelRead(), resulting in an out-of-bounds heap write. A malicious or compromised RDP client can exploit this to corrupt the heap and crash the server. Fixed in FreeRDP 3.29.0.
Severity
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-191 - Integer Underflow (Wrap or Wraparound)
Assigner
References
Impacted products
Vendor Product Version
FreeRDP FreeRDP Affected: 0 , < 3.29.0 (semver)
Unaffected: 3.29.0 (semver)
Create a notification for this product.
Date Public
2026-07-15 00:00
Credits
1121984919
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "FreeRDP",
          "vendor": "FreeRDP",
          "versions": [
            {
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              "status": "affected",
              "version": "0",
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            },
            {
              "status": "unaffected",
              "version": "3.29.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "cpeApplicability": [
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          "nodes": [
            {
              "cpeMatch": [
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                  "criteria": "cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "3.29.0",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
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      "credits": [
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          "type": "reporter",
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        }
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      "datePublic": "2026-07-15T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "FreeRDP versions 3.28.0 and earlier contain a heap buffer overflow in the server-side RAIL channel handler (rail_server_handle_messages() in channels/rail/server/rail_main.c). When processing a RAIL PDU header, the code subtracts RAIL_PDU_HEADER_LENGTH from the peer-controlled orderLength field without first verifying orderLength is at least the header length. For orderLength values 0..3 this causes an unsigned integer underflow to a very large size, which bypasses the Stream_EnsureRemainingCapacity() capacity check (due to pointer arithmetic wraparound) and is then passed to WTSVirtualChannelRead(), resulting in an out-of-bounds heap write. A malicious or compromised RDP client can exploit this to corrupt the heap and crash the server. Fixed in FreeRDP 3.29.0."
        }
      ],
      "metrics": [
        {
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            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 8.7,
            "baseSeverity": "HIGH",
            "exploitMaturity": "NOT_DEFINED",
            "privilegesRequired": "NONE",
            "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:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
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        {
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            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          },
          "format": "CVSS"
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      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-191",
              "description": "Integer Underflow (Wrap or Wraparound)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-01T12:22:18.323Z",
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck"
      },
      "references": [
        {
          "name": "GitHub Security Advisory (GHSA-qmvw-52ph-q5pv)",
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-qmvw-52ph-q5pv"
        },
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          "tags": [
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          "url": "https://github.com/FreeRDP/FreeRDP/commit/5370fb26fbf034ecd11d3026b6ad639b5fff493f"
        },
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        },
        {
          "name": "VulnCheck Advisory: FreeRDP 3.28.0 Heap Buffer Overflow via RAIL orderLength Underflow",
          "tags": [
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        }
      ],
      "title": "FreeRDP 3.28.0 Heap Buffer Overflow via RAIL orderLength Underflow",
      "x_generator": {
        "engine": "vulncheck-endgame"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-67298",
    "datePublished": "2026-08-01T12:22:18.323Z",
    "dateReserved": "2026-07-29T13:04:41.947Z",
    "dateUpdated": "2026-08-01T12:22:18.323Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}



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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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