CVE-2019-8263

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.

• CWE-121
• CWE-787

• https://cert-portal.siemens.com/productcert/pdf/ssa-286838.pdf
• https://cert-portal.siemens.com/productcert/pdf/ssa-927095.pdfThird Party Advisory
• https://cert-portal.siemens.com/productcert/pdf/ssa-940818.pdf
• https://ics-cert.kaspersky.com/advisories/klcert-advisories/2019/03/01/klcert-19-009-ultravnc-access-of-memory-location-after-end-of-buffer/Not Applicable, Third Party Advisory
• https://ics-cert.kaspersky.com/advisories/klcert-advisories/2019/03/01/klcert-19-010-ultravnc-stack-based-buffer-overflow/Third Party Advisory
• https://us-cert.cisa.gov/ics/advisories/icsa-21-131-11
• https://www.us-cert.gov/ics/advisories/icsa-20-161-06Third Party Advisory, US Government Resource
• https://cert-portal.siemens.com/productcert/pdf/ssa-286838.pdf
• https://cert-portal.siemens.com/productcert/pdf/ssa-927095.pdfThird Party Advisory
• https://cert-portal.siemens.com/productcert/pdf/ssa-940818.pdf
• https://ics-cert.kaspersky.com/advisories/klcert-advisories/2019/03/01/klcert-19-009-ultravnc-access-of-memory-location-after-end-of-buffer/Not Applicable, Third Party Advisory
• https://ics-cert.kaspersky.com/advisories/klcert-advisories/2019/03/01/klcert-19-010-ultravnc-stack-based-buffer-overflow/Third Party Advisory
• https://us-cert.cisa.gov/ics/advisories/icsa-21-131-11
• https://www.us-cert.gov/ics/advisories/icsa-20-161-06Third Party Advisory, US Government Resource

Published

Mar 5, 2019

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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