How severe is CVE-2019-8277?

CVE-2019-8277 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 high, integrity none, and availability none.

Is CVE-2019-8277 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-2019-8277?

CVE-2019-8277 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-2019-8277?

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-2019-8277 published?

CVE-2019-8277 was published on 2019-03-08 and last updated on 2026-06-17.

CVE-2019-8277

CVE-2019-8277 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-665.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 3% (86th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-665
Affected product: Uvnc Ultravnc
Published: 2019-03-08
Last modified: 2026-06-17

Description

UltraVNC revision 1211 contains multiple memory leaks (CWE-665) in VNC server code, which allows an attacker to read stack memory and can be abused for information disclosure. Combined with another vulnerability, it can be used to leak stack memory and bypass ASLR. This attack appears to be exploitable via network connectivity. These vulnerabilities have been fixed in revision 1212.

Frequently asked questions

What is CVE-2019-8277?: UltraVNC revision 1211 contains multiple memory leaks (CWE-665) in VNC server code, which allows an attacker to read stack memory and can be abused for information disclosure. Combined with another vulnerability, it can be used to leak stack memory and bypass ASLR. This attack appears to be exploitable via network connectivity. These vulnerabilities have been fixed in revision 1212.
How severe is CVE-2019-8277?: CVE-2019-8277 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 high, integrity none, and availability none.
Is CVE-2019-8277 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-2019-8277?: CVE-2019-8277 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-2019-8277?: 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-2019-8277 published?: CVE-2019-8277 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:*:*:*:*:*:*:*:*

More vulnerabilities in Uvnc Ultravnc

CVE-2019-8280 — Critical (CVSS 9.8): UltraVNC revision 1203 has out-of-bounds access vulnerability in VNC client inside RAW decoder, which can potentially…
CVE-2019-8275 — Critical (CVSS 9.8): UltraVNC revision 1211 has multiple improper null termination vulnerabilities in VNC server code, which result in…
CVE-2019-8274 — Critical (CVSS 9.8): UltraVNC revision 1211 has a heap buffer overflow vulnerability in VNC server code inside file transfer offer handler,…
CVE-2019-8273 — Critical (CVSS 9.8): UltraVNC revision 1211 has a heap buffer overflow vulnerability in VNC server code inside file transfer request…
CVE-2019-8272 — Critical (CVSS 9.8): UltraVNC revision 1211 has multiple off-by-one vulnerabilities in VNC server code, which can potentially result in code…
CVE-2019-8271 — Critical (CVSS 9.8): UltraVNC revision 1211 has a heap buffer overflow vulnerability in VNC server code inside file transfer handler, which…

All CVEs affecting Uvnc Ultravnc →

Other CWE-665 (Improper Initialization) vulnerabilities

CVE-2021-33635 — Critical (CVSS 9.8): When malicious images are pulled by isula pull, attackers can execute arbitrary code.
CVE-2022-37128 — Critical (CVSS 9.8): In D-Link DIR-816 A2_v1.10CNB04.img the network can be initialized without authentication via /goform/wizard_end.
CVE-2021-41264 — Critical (CVSS 9.8): OpenZeppelin Contracts is a library for smart contract development. In affected versions upgradeable contracts using…
CVE-2019-10196 — Critical (CVSS 9.8): A flaw was found in http-proxy-agent, prior to version 2.1.0. It was discovered http-proxy-agent passes an auth option…
CVE-2015-8367 — Critical (CVSS 9.8): The phase_one_correct function in Libraw before 0.17.1 allows attackers to cause memory errors and possibly execute…
CVE-2019-14271 — Critical (CVSS 9.8): In Docker 19.03.x before 19.03.1 linked against the GNU C Library (aka glibc), code injection can occur when the…

Browse all CWE-665 (Improper Initialization) vulnerabilities →