How severe is CVE-2019-15681?

CVE-2019-15681 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-2019-15681 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-15681?

CVE-2019-15681 primarily affects Libvnc Project Libvncserver. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-15681?

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-2019-15681 published?

CVE-2019-15681 was published on 2019-10-29 and last updated on 2026-06-17.

CVE-2019-15681

CVE-2019-15681 is a high-severity vulnerability in Libvnc Project Libvncserver 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% (87th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-665
Affected product: Libvnc Project Libvncserver
Published: 2019-10-29
Last modified: 2026-06-17

Description

LibVNC commit before d01e1bb4246323ba6fcee3b82ef1faa9b1dac82a contains a memory leak (CWE-655) in VNC server code, which allow 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 appear to be exploitable via network connectivity. These vulnerabilities have been fixed in commit d01e1bb4246323ba6fcee3b82ef1faa9b1dac82a.

Frequently asked questions

What is CVE-2019-15681?: LibVNC commit before d01e1bb4246323ba6fcee3b82ef1faa9b1dac82a contains a memory leak (CWE-655) in VNC server code, which allow 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 appear to be exploitable via network connectivity. These vulnerabilities have been fixed in commit d01e1bb4246323ba6fcee3b82ef1faa9b1dac82a.
How severe is CVE-2019-15681?: CVE-2019-15681 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-2019-15681 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-15681?: CVE-2019-15681 primarily affects Libvnc Project Libvncserver. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-15681?: 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-2019-15681 published?: CVE-2019-15681 was published on 2019-10-29 and last updated on 2026-06-17.

References

Affected products (14)

cpe:2.3:a:libvnc_project:libvncserver:*:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:esm:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:18.10:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_itc1500_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_itc1500_pro_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_itc1900_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_itc1900_pro_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_itc2200_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_itc2200_pro_firmware:*:*:*:*:*:*:*:*

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