// For flags

CVE-2019-15690

libvncserver: HandleCursorShape() integer overflow resulting in heap-based buffer overflow

Severity Score

8.8
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

Track*
*SSVC
Descriptions

LibVNCServer 0.9.12 release and earlier contains heap buffer overflow vulnerability within the HandleCursorShape() function in libvncclient/cursor.c. An attacker sends cursor shapes with specially crafted dimensions, which can result in remote code execution.

A flaw was found in libvncserver. An integer overflow within the HandleCursorShape() function can be exploited to cause a heap-based buffer overflow by tricking a user or application using libvncserver to connect to an unstrusted server and subsequently send cursor shapes with specially crafted dimensions. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

LibVNCServer is a C library that enables you to implement VNC server functionality into own programs. Issues addressed include a buffer overflow vulnerability.

*Credits: Pavel Cheremushkin from Kaspersky
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Attack Vector
Network
Attack Complexity
Low
Authentication
None
Confidentiality
Complete
Integrity
Complete
Availability
Complete
Attack Vector
Network
Attack Complexity
Low
Authentication
None
Confidentiality
Partial
Integrity
Partial
Availability
Partial
* Common Vulnerability Scoring System
SSVC
  • Decision:Track*
Exploitation
None
Automatable
No
Tech. Impact
Total
* Organization's Worst-case Scenario
Timeline
  • 2019-08-27 CVE Reserved
  • 2020-03-23 CVE Published
  • 2025-01-24 CVE Updated
  • 2025-04-02 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-122: Heap-based Buffer Overflow
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
LibVNC
Search vendor "LibVNC"
 LibVNCServer
Search vendor "LibVNC" for product "LibVNCServer"
 <= 0.9.12
Search vendor "LibVNC" for product "LibVNCServer" and version " <= 0.9.12"
en
Affected