CVE-2006-1652

CVE-2006-1652 is a critical-severity vulnerability in Ultravnc Tabbed Viewer with a CVSS 2.0 base score of 9.0. Its EPSS exploit-prediction score of 67% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-119.

Key facts

Description

Multiple buffer overflows in (a) UltraVNC (aka Ultr@VNC) 1.0.1 and earlier and (b) tabbed_viewer 1.29 (1) allow user-assisted remote attackers to execute arbitrary code via a malicious server that sends a long string to a client that connects on TCP port 5900, which triggers an overflow in Log::ReallyPrint; and (2) allow remote attackers to cause a denial of service (server crash) via a long HTTP GET request to TCP port 5800, which triggers an overflow in VNCLog::ReallyPrint.

Frequently asked questions

What is CVE-2006-1652?
Multiple buffer overflows in (a) UltraVNC (aka Ultr@VNC) 1.0.1 and earlier and (b) tabbed_viewer 1.29 (1) allow user-assisted remote attackers to execute arbitrary code via a malicious server that sends a long string to a client that connects on TCP port 5900, which triggers an overflow in Log::ReallyPrint; and (2) allow remote attackers to cause a denial of service (server crash) via a long HTTP GET request to TCP port 5800, which triggers an overflow in VNCLog::ReallyPrint.
How severe is CVE-2006-1652?
CVE-2006-1652 has a CVSS 2.0 base score of 9.0, rated critical severity.
Is CVE-2006-1652 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 67% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2006-1652?
CVE-2006-1652 primarily affects Ultravnc Tabbed Viewer. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2006-1652?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2006-1652 published?
CVE-2006-1652 was published on 2006-04-06 and last updated on 2026-06-16.

References

Affected products (2)

Other CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) vulnerabilities

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