How severe is CVE-2019-8276?

CVE-2019-8276 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2019-8276 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-8276?

CVE-2019-8276 primarily affects Uvnc Ultravnc. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-8276?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2019-8276 published?

CVE-2019-8276 was published on 2019-03-08 and last updated on 2026-06-17.

CVE-2019-8276

CVE-2019-8276 is a high-severity vulnerability in Uvnc Ultravnc with a CVSS 3.x base score of 7.5. 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-787.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 6% (92nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Uvnc Ultravnc
Published: 2019-03-08
Last modified: 2026-06-17

Description

UltraVNC revision 1211 has a stack buffer overflow vulnerability in VNC server code inside file transfer request handler, which can result in Denial of Service (DoS). This attack appears to be exploitable via network connectivity. This vulnerability has been fixed in revision 1212.

Frequently asked questions

What is CVE-2019-8276?: UltraVNC revision 1211 has a stack buffer overflow vulnerability in VNC server code inside file transfer request handler, which can result in Denial of Service (DoS). This attack appears to be exploitable via network connectivity. This vulnerability has been fixed in revision 1212.
How severe is CVE-2019-8276?: CVE-2019-8276 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2019-8276 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-8276?: CVE-2019-8276 primarily affects Uvnc Ultravnc. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-8276?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2019-8276 published?: CVE-2019-8276 was published on 2019-03-08 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:uvnc:ultravnc:*:*:*:*:*:*:*:*
cpe:2.3:a:siemens:sinumerik_access_mymachine\/p2p:*:*:*:*:*:*:*:*
cpe:2.3:a:siemens:sinumerik_pcu_base_win10_software\/ipc:*:*:*:*:*:*:*:*
cpe:2.3:a:siemens:sinumerik_pcu_base_win7_software\/ipc:*:*:*:*:*:*:*:*

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