LibVNCServer versions 0.9.15 and prior (fixed in commit 009008e) contain a heap out-of-bounds read vulnerability in the UltraZip encoding handler that allows a malicious VNC server to cause information disclosure or application crash. Attackers can exploit improper bounds checking in the HandleUltraZipBPP() function by manipulating subrectangle header counts to read beyond the allocated heap buffer.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
Low
Partial data leak
Integrity
None
No data modification
Availability
Low
Partial disruption
CVSS Vector v4.0
Weakness Type (CWE)
Vulnerable Products 1
| Configuration | From (including) | Up to (excluding) |
|---|---|---|
|
Libvncserver_Project Libvncserver
cpe:2.3:a:libvncserver_project:libvncserver:*:*:*:*:*:*:*:*
|
— |
0.9.15
|
References 3
https://github.com/LibVNC/libvncserver/commit/009008e2f4d5a54dd71f422070df3af7b…
disclosure@vulncheck.com
https://github.com/LibVNC/libvncserver/security/advisories/GHSA-87q7-v983-qwcj
disclosure@vulncheck.com
https://www.vulncheck.com/advisories/libvncserver-ultrazip-encoding-heap-out-of…
disclosure@vulncheck.com