Description
Multiple integer signedness errors in (1) UltraVNC 1.0.2 and 1.0.5 and (2) TightVnc 1.3.9 allow remote VNC servers to cause a denial of service (heap corruption and application crash) or possibly execute arbitrary code via a large length value in a message, related to the (a) ClientConnection::CheckBufferSize and (b) ClientConnection::CheckFileZipBufferSize functions in ClientConnection.cpp.
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.
Exploit-DB 2
- TightVNC - Authentication Failure Integer Overflow (PoC) EDB-8024 · dos · Feb 9, 2009 · verified
- UltraVNC/TightVNC (Multiple VNC Clients) - Multiple Integer Overflows (PoC) EDB-7990 · dos · Feb 4, 2009 · verified
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
References
- http://forum.ultravnc.info/viewtopic.php?t=14654
- http://vnc-tight.svn.sourceforge.net/viewvc/vnc-tight?view=rev&revision=3564
- ADV-2009-0321 vdb-entry
- 33568 vdb-entry
- 20090203 CORE-2008-1009 - VNC Multiple Integer Overflows mailing-list
- 8024 exploit
- http://www.coresecurity.com/content/vnc-integer-overflows
- ADV-2009-0322 vdb-entry
- 7990 exploit
- 33807 third-party-advisory