How severe is CVE-2019-8264?

CVE-2019-8264 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2019-8264 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-8264?

CVE-2019-8264 affects Uvnc Ultravnc. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-8264?

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-2019-8264 published?

CVE-2019-8264 was published on 2019-03-08 and last updated on 2026-06-17.

CVE-2019-8264

CVE-2019-8264 is a critical-severity vulnerability in Uvnc Ultravnc with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-125.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 3% (86th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-125
Affected product: Uvnc Ultravnc
Published: 2019-03-08
Last modified: 2026-06-17

Description

UltraVNC revision 1203 has out-of-bounds access vulnerability in VNC client inside Ultra2 decoder, which can potentially result in code execution. This attack appears to be exploitable via network connectivity. This vulnerability has been fixed in revision 1204.

Frequently asked questions

What is CVE-2019-8264?: UltraVNC revision 1203 has out-of-bounds access vulnerability in VNC client inside Ultra2 decoder, which can potentially result in code execution. This attack appears to be exploitable via network connectivity. This vulnerability has been fixed in revision 1204.
How severe is CVE-2019-8264?: CVE-2019-8264 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2019-8264 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-8264?: CVE-2019-8264 affects Uvnc Ultravnc. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-8264?: 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-2019-8264 published?: CVE-2019-8264 was published on 2019-03-08 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:uvnc:ultravnc:*:*:*:*:*:*:*:*

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