How severe is CVE-2008-4770?

CVE-2008-4770 has a CVSS 2.0 base score of 10.0, rated critical severity.

Is CVE-2008-4770 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2008-4770?

CVE-2008-4770 primarily affects Realvnc. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2008-4770?

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-2008-4770 published?

CVE-2008-4770 was published on 2009-01-16 and last updated on 2026-06-16.

CVE-2008-4770

CVE-2008-4770 is a critical-severity vulnerability in Realvnc 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. The underlying weakness is classified as CWE-20.

Key facts

Severity: Critical (CVSS 2.0 base score 10.0)
EPSS exploit prediction: 4% (89th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Realvnc
Published: 2009-01-16
Last modified: 2026-06-16

Description

The CMsgReader::readRect function in the VNC Viewer component in RealVNC VNC Free Edition 4.0 through 4.1.2, Enterprise Edition E4.0 through E4.4.2, and Personal Edition P4.0 through P4.4.2 allows remote VNC servers to execute arbitrary code via crafted RFB protocol data, related to "encoding type."

Frequently asked questions

What is CVE-2008-4770?: The CMsgReader::readRect function in the VNC Viewer component in RealVNC VNC Free Edition 4.0 through 4.1.2, Enterprise Edition E4.0 through E4.4.2, and Personal Edition P4.0 through P4.4.2 allows remote VNC servers to execute arbitrary code via crafted RFB protocol data, related to "encoding type."
How severe is CVE-2008-4770?: CVE-2008-4770 has a CVSS 2.0 base score of 10.0, rated critical severity.
Is CVE-2008-4770 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2008-4770?: CVE-2008-4770 primarily affects Realvnc. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2008-4770?: 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-2008-4770 published?: CVE-2008-4770 was published on 2009-01-16 and last updated on 2026-06-16.

References

Affected products (6)

cpe:2.3:a:realvnc:realvnc:4.0:*:free:*:*:*:*:*
cpe:2.3:a:realvnc:realvnc:4.1.2:*:free:*:*:*:*:*
cpe:2.3:a:realvnc:realvnc:4.4.2:*:enterprise:*:*:*:*:*
cpe:2.3:a:realvnc:realvnc:e4.0:*:enterprise:*:*:*:*:*
cpe:2.3:a:realvnc:realvnc:p4.0:*:personal:*:*:*:*:*
cpe:2.3:a:realvnc:realvnc:p4.4.2:*:personal:*:*:*:*:*

More vulnerabilities in Realvnc

CVE-2013-6886 — High (CVSS 7.2): RealVNC VNC 5.0.6 on Mac OS X, Linux, and UNIX allows local users to gain privileges via a crafted argument to the (1)…

All CVEs affecting Realvnc →

Other CWE-20 (Improper Input Validation) vulnerabilities

CVE-2026-48316 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
CVE-2026-48281 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
CVE-2026-48277 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
CVE-2026-48055 — Critical (CVSS 10.0): Streambert is a cross-platform Electron Desktop App to stream and download any video media. In versions 2.4.0 and…
CVE-2026-34910 — Critical (CVSS 10.0): A malicious actor with access to the network could exploit an Improper Input Validation vulnerability found in UniFi OS…
CVE-2026-33587 — Critical (CVSS 10.0): Lack of user input sanitisation in Open Notebook v1.8.3 allows the application user to execute Python code (and…

Browse all CWE-20 (Improper Input Validation) vulnerabilities →