CVE-2019-8266
UltraVNC revision 1207 has multiple out-of-bounds access vulnerabilities connected with improper...
UltraVNC revision 1207 has multiple out-of-bounds access vulnerabilities connected with improper usage of ClientConnection::Copybuffer function in VNC client code, which can potentially result in code execution. This attack appears to be exploitable via network connectivity. User interaction is required to trigger these vulnerabilities. These vulnerabilities have been fixed in revision 1208.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
UltraVNC revision 1207 has multiple out-of-bounds access vulnerabilities connected with improper usage of ClientConnection::Copybuffer function in VNC client code, which can potentially result in code execution. This attack appears to be exploitable via network connectivity. User interaction is required to trigger these vulnerabilities. These vulnerabilities have been fixed in revision 1208.
- Record
CVE-2019-8266- CVSS 3.0
- 9.8 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 7.5 High
AV:N/AC:L/Au:N/C:P/I:P/A:P - Weakness
- CWE-788, CWE-125, CWE-787
- Updated
- 2026-11-02
CVE List No score
UltraVNC revision 1207 has multiple out-of-bounds access vulnerabilities connected with improper usage of ClientConnection::Copybuffer function in VNC client code, which can potentially result in code execution. This attack appears to be exploitable via network connectivity. User interaction is required to trigger these vulnerabilities. These vulnerabilities have been fixed in revision 1208.
- Record
CVE-2019-8266- Weakness
- CWE-788
- Updated
- 2026-11-02
EUVDEUVD-2019-17664 No score
UltraVNC revision 1207 has multiple out-of-bounds access vulnerabilities connected with improper usage of ClientConnection::Copybuffer function in VNC client code, which can potentially result in code execution. This attack appears to be exploitable via network connectivity. User interaction is required to trigger these vulnerabilities. These vulnerabilities have been fixed in revision 1208.
- Record
EUVD-2019-17664- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-h88h-84v5-wrjr
UltraVNC revision 1207 has multiple out-of-bounds access vulnerabilities connected with improper...
UltraVNC revision 1207 has multiple out-of-bounds access vulnerabilities connected with improper usage of ClientConnection::Copybuffer function in VNC client code, which can potentially result in code execution. This attack appears to be exploitable via network connectivity. User interaction is required to trigger these vulnerabilities. These vulnerabilities have been fixed in revision 1208.
- Record
GHSA-h88h-84v5-wrjr- CVSS 3.0
- 9.8 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-125
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2019-8266 is a critical vulnerability (CVSS 9.8) in Kaspersky Lab Ultravnc, published March 8, 2019. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.84%, the 86th percentile. No source names a fixed version.
References
ics-cert.kaspersky.com/advisories/klcert-advisories/2019/03/01/klcert-19-013-ultravnc-access-of-memory-location-after-end-of-buffer
cert-portal.siemens.com/productcert/pdf/ssa-927095.pdf
us-cert.gov/ics/advisories/icsa-20-161-06
nvd.nist.gov/vuln/detail/CVE-2019-8266
github.com/advisories/GHSA-h88h-84v5-wrjr