Stack-based buffer overflow in Kaspersky Lab UltraVNC
Priority LOW 34CWE-121Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-121 and the CVSS impact.
Summary
UltraVNC revision 1205 has stack-based buffer overflow vulnerability in VNC client code inside ShowConnInfo routine, which leads to a denial of service (DoS) condition. This attack appear to be exploitable via network connectivity. User interaction is required to trigger this vulnerability. This vulnerability has been fixed in revision 1206.
Why it matters now
EPSS 0.0248 84th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Kaspersky Lab | UltraVNC | 1.2.2.3 | — | No fix listed | CNA |
- UltraVNC VendorKaspersky Lab Affected 1.2.2.3 Fixed in — No fix listed CNA
CPE configurations NVD · 4
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:uvnc:ultravnc:*:*:*:*:*:*:*:* | before 1.2.2.3 | Vulnerable | uvnc |
| cpe:2.3:a:siemens:sinumerik_access_mymachine\/p2p:*:*:*:*:*:*:*:* | before 4.8 | Vulnerable | Siemens |
| cpe:2.3:a:siemens:sinumerik_pcu_base_win10_software\/ipc:*:*:*:*:*:*:*:* | before 14.00 | Vulnerable | Siemens |
| cpe:2.3:a:siemens:sinumerik_pcu_base_win7_software\/ipc:*:*:*:*:*:*:*:* | up to 12.01 | Vulnerable | Siemens |
- cpe:2.3:a:uvnc:ultravnc:*:*:*:*:*:*:*:* Versions before 1.2.2.3 Vulnerable ·uvnc
- cpe:2.3:a:siemens:sinumerik_access_mymachine\/p2p:*:*:*:*:*:*:*:* Versions before 4.8 Vulnerable ·Siemens
- cpe:2.3:a:siemens:sinumerik_pcu_base_win10_software\/ipc:*:*:*:*:*:*:*:* Versions before 14.00 Vulnerable ·Siemens
- cpe:2.3:a:siemens:sinumerik_pcu_base_win7_software\/ipc:*:*:*:*:*:*:*:* Versions up to 12.01 Vulnerable ·Siemens
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2019-8263
- 2026-10-03 Alias added: GHSA-3ccg-xj7w-w764
References
Advisory 4
- https://ics-cert.kaspersky.com/advisories/klcert-advisories/2019/03/01/klcert-19-009-ultravnc-access-of-memory-location-after-end-of-buffer/
- https://ics-cert.kaspersky.com/advisories/klcert-advisories/2019/03/01/klcert-19-010-ultravnc-stack-based-buffer-overflow/
- https://cert-portal.siemens.com/productcert/pdf/ssa-927095.pdf
- https://www.us-cert.gov/ics/advisories/icsa-20-161-06
More Kaspersky Lab vulnerabilities
- TI-2005-02970 Heap-based buffer overflow in Kaspersky Antivirus (KAV) 5.0 and Kaspersky Personal… CVSS 2.0HIGH 10.0
- TI-2004-00844 McAfee Anti-Virus Engine DATS drivers before 4398 released on Oct 13th 2004 and DATS… CVSS 2.0HIGH 7.5
- TI-2007-00432 Heap-based buffer overflow in the arj.ppl module in the OnDemand Scanner in Kaspersky… CVSS 2.0HIGH 10.0
- TI-2019-05946 Heap-based buffer overflow in Kaspersky Lab UltraVNC CVSS 3.1CRITICAL 9.8
- TI-2019-05945 Heap-based buffer overflow in Kaspersky Lab UltraVNC CVSS 3.1CRITICAL 9.8
- TI-2019-05943 Heap-based buffer overflow in Kaspersky Lab UltraVNC CVSS 3.1CRITICAL 9.8
Sources
- CVE-2019-8263 · CVE Program
- CVE-2019-8263 · NVD
- FIRST EPSS
- GHSA-3ccg-xj7w-w764 · GitHub Advisory Database · CC BY 4.0
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