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TI-2019-05931 Aliases CVE-2019-8259GHSA-mhxq-j55c-q97g

Memory leak in UltraVNC

Priority LOW 38CWE-665Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
High · None · None
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-401.

Summary

UltraVNC revision 1198 contains multiple memory leaks (CWE-655) in VNC client code, which allow an attacker to read stack memory and can be abused for information disclosure. Combined with another vulnerability, it can be used to leak stack memory and bypass ASLR. This attack appears to be exploitable via network connectivity. These vulnerabilities have been fixed in revision 1199.

Why it matters now

EPSS 0.03009 87th 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

VendorProductAffected versionsFixed inStatusSource
UltraVNCUltraVNC1.2.2.3—No fix listedCNA
  • UltraVNC VendorUltraVNC Affected 1.2.2.3 Fixed in — No fix listed CNA

CPE configurations NVD · 4

CPEVersionsRoleVendor
cpe:2.3:a:uvnc:ultravnc:*:*:*:*:*:*:*:*before 1.2.2.3Vulnerableuvnc
cpe:2.3:a:siemens:sinumerik_access_mymachine\/p2p:*:*:*:*:*:*:*:*before 4.8VulnerableSiemens
cpe:2.3:a:siemens:sinumerik_pcu_base_win10_software\/ipc:*:*:*:*:*:*:*:*before 14.00VulnerableSiemens
cpe:2.3:a:siemens:sinumerik_pcu_base_win7_software\/ipc:*:*:*:*:*:*:*:*up to 12.01VulnerableSiemens
  • 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

  1. 2026-10-02 Threatist record created from CVE-2019-8259
  2. 2026-10-03 Alias added: GHSA-mhxq-j55c-q97g

References

Advisory 3

Other 3

  • TI-2006-01599 Multiple buffer overflows in (a) UltraVNC (aka Ultr@VNC) 1.0.1 and earlier and (b)… CVSS 2.0HIGH 9.0
  • TI-2008-00582 Stack-based buffer overflow in the ClientConnection::NegotiateProtocolVersion function in… CVSS 2.0HIGH 9.3
  • TI-2009-00368 Multiple integer signedness errors in (1) UltraVNC 1.0.2 and 1.0.5 and (2) TightVnc 1.3.9… CVSS 2.0HIGH 10.0
  • TI-2019-05934 Heap-based buffer overflow in UltraVNC CVSS 3.1CRITICAL 9.8
  • TI-2019-05930 Heap-based buffer overflow in UltraVNC CVSS 3.1CRITICAL 9.8
  • TI-2008-04755 Multiple stack-based buffer overflows in multiple functions in vncviewer/FileTransfer.cpp… CVSS 2.0HIGH 9.3
See all 13 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences