OESA-2026-4656 (CVE-2026-91953)

Vulnerability from osv_openeuler – Published: 2026-10-29 09:04 – Updated: 2026-10-29 09:04 – Source website
VLAI
Summary
freerdp security update
Details

FreeRDP is a client implementation of the Remote Desktop Protocol (RDP) that follows Microsoft's open specifications. This package provides the client applications xfreerdp.

Security Fix(es):

FreeRDP versions before 3.31.0 contain a heap buffer overflow vulnerability in nego_send_negotiation_request() that fails to validate the LB_LOAD_BALANCE_INFO field length before writing to a fixed 512-byte buffer. A malicious RDP server or man-in-the-middle can send a Server Redirection PDU with an oversized LB_LOAD_BALANCE_INFO value to overflow the buffer with attacker-controlled content, causing denial of service or heap corruption before authentication completes.(CVE-2026-91953)

FreeRDP before 3.31.0 contains an out-of-bounds read vulnerability in the URBDRC channel's func_get_ep_desc function that indexes interface arrays by position instead of protocol field InterfaceNumber. A malicious RDP server can send a crafted SELECT_CONFIGURATION message with permuted InterfaceNumber values to read past allocated heap memory and crash the client.(CVE-2026-91956)

FreeRDP is an implementation of the Remote Desktop Protocol (RDP) open sourced by the FreeRDP team. FreeRDP versions before 3.31.0 have a buffer error vulnerability. This vulnerability originates from buffer over-reading in the rts_read_result function in the RPC gateway transport parser. An attacker can trigger an out-of-bounds read by sending a specially crafted BIND_ACK PDU with truncated result entries, causing the process to terminate.(CVE-2026-91959)

FreeRDP versions before 3.31.0 contain an uninitialized heap memory disclosure vulnerability in the urbdrc USB redirection channel. A malicious RDP server can induce failing USB transfers to read uninitialized heap memory from the client, defeating ASLR and enabling remote code execution when chained with memory corruption vulnerabilities.(CVE-2026-91963)

FreeRDP versions before 3.31.0 contain a heap-based buffer overflow in nego_send_negotiation_request when processing Server Redirection PDU messages with attacker-controlled LoadBalanceInfo fields. A malicious RDP server can trigger the overflow by sending an arbitrary-length field that gets written to a fixed 512-byte buffer without validation, causing client crashes or potential code execution when chained with memory disclosure.(CVE-2026-91964)

Severity
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/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
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "aarch64": [
          "freerdp-2.11.8-11.oe2403sp4.aarch64.rpm",
          "freerdp-debuginfo-2.11.8-11.oe2403sp4.aarch64.rpm",
          "freerdp-debugsource-2.11.8-11.oe2403sp4.aarch64.rpm",
          "freerdp-devel-2.11.8-11.oe2403sp4.aarch64.rpm",
          "freerdp-help-2.11.8-11.oe2403sp4.aarch64.rpm",
          "libwinpr-2.11.8-11.oe2403sp4.aarch64.rpm",
          "libwinpr-devel-2.11.8-11.oe2403sp4.aarch64.rpm"
        ],
        "src": [
          "freerdp-2.11.8-11.oe2403sp4.src.rpm"
        ],
        "x86_64": [
          "freerdp-2.11.8-11.oe2403sp4.x86_64.rpm",
          "freerdp-debuginfo-2.11.8-11.oe2403sp4.x86_64.rpm",
          "freerdp-debugsource-2.11.8-11.oe2403sp4.x86_64.rpm",
          "freerdp-devel-2.11.8-11.oe2403sp4.x86_64.rpm",
          "freerdp-help-2.11.8-11.oe2403sp4.x86_64.rpm",
          "libwinpr-2.11.8-11.oe2403sp4.x86_64.rpm",
          "libwinpr-devel-2.11.8-11.oe2403sp4.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:24.03-LTS-SP4",
        "name": "freerdp",
        "purl": "pkg:rpm/openEuler/freerdp\u0026distro=openEuler-24.03-LTS-SP4"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.11.8-11.oe2403sp4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "severity": "High"
  },
  "details": "FreeRDP is a client implementation of the Remote Desktop Protocol (RDP) that follows Microsoft\u0026amp;apos;s open specifications. This package provides the client applications xfreerdp.\r\n\r\nSecurity Fix(es):\n\nFreeRDP versions before 3.31.0 contain a heap buffer overflow vulnerability in nego_send_negotiation_request() that fails to validate the LB_LOAD_BALANCE_INFO field length before writing to a fixed 512-byte buffer. A malicious RDP server or man-in-the-middle can send a Server Redirection PDU with an oversized LB_LOAD_BALANCE_INFO value to overflow the buffer with attacker-controlled content, causing denial of service or heap corruption before authentication completes.(CVE-2026-91953)\n\nFreeRDP before 3.31.0 contains an out-of-bounds read vulnerability in the URBDRC channel\u0026apos;s func_get_ep_desc function that indexes interface arrays by position instead of protocol field InterfaceNumber. A malicious RDP server can send a crafted SELECT_CONFIGURATION message with permuted InterfaceNumber values to read past allocated heap memory and crash the client.(CVE-2026-91956)\n\nFreeRDP is an implementation of the Remote Desktop Protocol (RDP) open sourced by the FreeRDP team.\n FreeRDP versions before 3.31.0 have a buffer error vulnerability. This vulnerability originates from buffer over-reading in the rts_read_result function in the RPC gateway transport parser. An attacker can trigger an out-of-bounds read by sending a specially crafted BIND_ACK PDU with truncated result entries, causing the process to terminate.(CVE-2026-91959)\n\nFreeRDP versions before 3.31.0 contain an uninitialized heap memory disclosure vulnerability in the urbdrc USB redirection channel. A malicious RDP server can induce failing USB transfers to read uninitialized heap memory from the client, defeating ASLR and enabling remote code execution when chained with memory corruption vulnerabilities.(CVE-2026-91963)\n\nFreeRDP versions before 3.31.0 contain a heap-based buffer overflow in nego_send_negotiation_request when processing Server Redirection PDU messages with attacker-controlled LoadBalanceInfo fields. A malicious RDP server can trigger the overflow by sending an arbitrary-length field that gets written to a fixed 512-byte buffer without validation, causing client crashes or potential code execution when chained with memory disclosure.(CVE-2026-91964)",
  "id": "OESA-2026-4656",
  "modified": "2026-10-29T09:04:07Z",
  "published": "2026-10-29T09:04:07Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-4656"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-91953"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-91956"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-91959"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-91963"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-91964"
    }
  ],
  "schema_version": "1.7.2",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/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",
      "type": "CVSS_V4"
    }
  ],
  "summary": "freerdp security update",
  "upstream": [
    "CVE-2026-91953",
    "CVE-2026-91956",
    "CVE-2026-91959",
    "CVE-2026-91963",
    "CVE-2026-91964"
  ]
}



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