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CVE-2026-91951 (GCVE-0-2026-91951)

Vulnerability from cvelistv5 – Published: 2026-09-15 15:18 – Updated: 2026-09-15 15:18
VLAI
Title
FreeRDP 3.14.0 through 3.30.0 Out-of-bounds Write via urbdrc
Summary
FreeRDP versions before 3.31.0 contain an out-of-bounds write vulnerability in the urbdrc client channel's urb_send_current_frame_number_result() function. A malicious RDP server can send a crafted 28-byte USB redirection message to trigger a 4-byte write past the allocated 16-byte buffer, causing denial of service when verbose asserts are enabled.
Severity
7.1 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
FreeRDP FreeRDP Affected: 3.14.0 , < 3.31.0 (semver)
Unaffected: 3.31.0 (semver)
    cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-09-01 00:00
Credits
dutchypoo
Show details on NVD website
To clipboard 

{
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              "versionType": "semver"
            }
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        }
      ],
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            "version": "3.1"
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      "problemTypes": [
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              "description": "Reachable Assertion",
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              "type": "CWE"
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        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck"
      },
      "references": [
        {
          "name": "GitHub Security Advisory (GHSA-h5w2-q35j-443h)",
          "tags": [
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          "url": "https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-h5w2-q35j-443h"
        },
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          "tags": [
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      "x_generator": {
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  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-91951",
    "datePublished": "2026-09-15T15:18:08.518Z",
    "dateReserved": "2026-09-15T11:07:34.398Z",
    "dateUpdated": "2026-09-15T15:18:08.518Z",
    "state": "PUBLISHED"
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    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-09-15T18:31:09+00:00",
      "cve": "CVE-2026-91951",
      "id": "CVE-2026-91951",
      "initial_release_date": "2026-09-15T15:18:08.518000+00:00",
      "product_status:known_affected": "7",
      "product_status:known_not_affected": "24",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "FreeRDP: FreeRDP: Denial of Service via out-of-bounds write in urbdrc client channel",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-91951.json",
      "version": "3"
    }
  }
}



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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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