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CVE-2026-91961 (GCVE-0-2026-91961)

Vulnerability from cvelistv5 – Published: 2026-09-15 15:18 – Updated: 2026-09-15 15:18
VLAI
Title
FreeRDP before 3.31.0 Denial of Service via URBDRC
Summary
FreeRDP before 3.31.0 contains a denial-of-service vulnerability in the URBDRC control-transfer request path that fails to validate OutputBufferSize before forwarding to the libusb backend. A malicious RDP server can send a control-transfer request with OutputBufferSize set to 65536, triggering a reachable assertion that terminates the client process.
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: 0 , < 3.31.0 (semver)
Unaffected: 3.31.0 (semver)
    cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-08-31 00:00
Credits
gulamovzavohir02-glitch
Show details on NVD website
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{
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    "dateReserved": "2026-09-15T11:08:44.670Z",
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    "redhat_vex": {
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      "cve": "CVE-2026-91961",
      "id": "CVE-2026-91961",
      "initial_release_date": "2026-09-15T15:18:15.292000+00:00",
      "product_status:known_affected": "31",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "FreeRDP: FreeRDP: Denial of Service via URBDRC control-transfer request with invalid OutputBufferSize",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-91961.json",
      "version": "3"
    }
  }
}



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Sightings

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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.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • 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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