CVE-2026-107612

Incorrect permission assignment in GlavSoft TightVNC Server for Windows before 2.8.88 allows a local authenticated user to read or overwrite the inter-process communication handles used between the TightVNC service and its desktop server process. The named shared memory segment in the Global\ namespace that carries the pipe HANDLE values is created with a NULL DACL, and its name is derived from a time-seeded srand(time(0)) value that is predictable to one-second granularity. A low-privileged local process can open the mapping and tamper with the IPC channel of a service running as SYSTEM, potentially leading to disclosure of session data, privilege escalation, or denial of service.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://sourceforge.net/p/vnc-tight/bugs/1658/
https://www.tightvnc.com/whatsnew.php

Configurations

No configuration.

History

08 Oct 2026, 14:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-08 14:16

Updated : 2026-10-08 21:10

NVD link : CVE-2026-107612

Mitre link : CVE-2026-107612

CVE.ORG link : CVE-2026-107612

JSON object : View

Products Affected

No product.

CWE

CWE-338

Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)

CWE-732

Incorrect Permission Assignment for Critical Resource

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