HOMEVULNERABILITIESCVE-2016-5673
HIGH

CVE-2016-5673

CWE-284Published: August 25, 2016· Updated: Jun 17, 2026

7.5
CVSS v3.1

Official Description

UltraVNC Repeater before 1300 does not restrict destination IP addresses or TCP ports, which allows remote attackers to obtain open-proxy functionality by using a :: substring in between the IP address and port number.

NVD Source

Technical Analysis

CVE-2016-5673 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in full integrity compromise (data manipulation), with a CVSS base score of 7.5.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.None
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityNone
IntegrityHigh
AvailabilityNone
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Affected Vendors & Products

ultravnc1 product(s)
repeater
Source: NVD CPE · 1 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
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Official Patches & Advisories

All References (6)

http://www.kb.cert.org/vuls/id/735416Third Party Advisory · US Government Resource
http://www.kb.cert.org/vuls/id/BLUU-A9WQVPThird Party Advisory · US Government Resource
http://www.kb.cert.org/vuls/id/735416Third Party Advisory · US Government Resource
http://www.kb.cert.org/vuls/id/BLUU-A9WQVPThird Party Advisory · US Government Resource

Quick Facts

CVE IDCVE-2016-5673
CVSS Score7.5 / 10
SeverityHIGH
WeaknessCWE-284
CISA KEVNo
Affected1 vendor(s)
PublishedAug 25, 2016

Related CVEs (CWE-284)

Recommended Actions

  • Apply vendor patches immediately
  • Monitor CVE-2016-5673 in threat intel feeds
  • Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.