CVE-2026-91964

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.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-2vf2-grvj-6g8x
https://www.vulncheck.com/advisories/freerdp-2.0.0-through-3.30.0-heap-buffer-overflow-via-routingtoken

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-15 16:17

Updated : 2026-09-16 04:18

NVD link : CVE-2026-91964

Mitre link : CVE-2026-91964

CVE.ORG link : CVE-2026-91964

JSON object : View

Products Affected

No product.

CWE

CWE-122

Heap-based Buffer Overflow

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