Vulnerability · Published Nov 23, 2021 · Assigned by GovTech CSG
CVE-2021-42785Buffer Overflow in tvnviewer.exe via Crafted Packet in TightVNC Viewer 2.8.59
Critical 9.8
In plain English
A critical-severity buffer overflow in TightVNC Viewer from GlavSoft LLC. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 2.3% (higher than 84% of all known vulnerabilities).
Severity (CVSS NVD)9.8Critical
Exploit odds (30 days)2.3%top 16.3% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known
Official description
Buffer Overflow vulnerability in tvnviewer.exe of TightVNC Viewer allows a remote attacker to execute arbitrary instructions via a crafted FramebufferUpdate packet from a VNC server.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| GlavSoft LLC | TightVNC Viewer | 2.8.59 – through 2.8.59 |
Weakness: CWE-120
References
- https://www.tightvnc.com/whatsnew.php x_refsource_MISC