How severe is CVE-2006-2206?

CVE-2006-2206 has a CVSS 2.0 base score of 10.0, rated critical severity.

Is CVE-2006-2206 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2006-2206?

CVE-2006-2206 affects Ultravnc. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2006-2206?

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-2006-2206 published?

CVE-2006-2206 was published on 2006-05-05 and last updated on 2026-06-16.

CVE-2006-2206

CVE-2006-2206 is a critical-severity vulnerability in Ultravnc with a CVSS 2.0 base score of 10.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Critical (CVSS 2.0 base score 10.0)
EPSS exploit prediction: 2% (80th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Ultravnc
Published: 2006-05-05
Last modified: 2026-06-16

Description

The MS-Logon authentication scheme in UltraVNC (aka Ultr@VNC) 1.0.1 uses weak encryption (XOR) for challenge/response, which allows remote attackers to gain privileges by sniffing and decrypting passwords.

Frequently asked questions

What is CVE-2006-2206?: The MS-Logon authentication scheme in UltraVNC (aka Ultr@VNC) 1.0.1 uses weak encryption (XOR) for challenge/response, which allows remote attackers to gain privileges by sniffing and decrypting passwords.
How severe is CVE-2006-2206?: CVE-2006-2206 has a CVSS 2.0 base score of 10.0, rated critical severity.
Is CVE-2006-2206 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2006-2206?: CVE-2006-2206 affects Ultravnc. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2006-2206?: 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-2006-2206 published?: CVE-2006-2206 was published on 2006-05-05 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:a:ultravnc:ultravnc:1.0.1:*:*:*:*:*:*:*

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