CVE-2026-91948

FreeRDP versions before 3.31.0 contain an out-of-bounds write vulnerability in server-side static virtual channel handling when CHANNEL_OPTION_SHOW_PROTOCOL is enabled. Authenticated clients can queue oversized channel messages that cause buffer underflow and corrupt heap memory including live pointers, potentially enabling code execution.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.6 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/FreeRDP/FreeRDP/commit/40d9202cd95551600c07437ce6bd5ecd7d31e57b
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-9jcm-x588-gh26
https://www.vulncheck.com/advisories/freerdp-before-3.31.0-out-of-bounds-write-via-show-protocol
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-9jcm-x588-gh26

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-15 16:17

Updated : 2026-09-16 04:18

NVD link : CVE-2026-91948

Mitre link : CVE-2026-91948

CVE.ORG link : CVE-2026-91948

JSON object : View

Products Affected

No product.

CWE

CWE-191

Integer Underflow (Wrap or Wraparound)

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