libvncserver: HandleCursorShape() integer overflow resulting in heap-based buffer overflow
Published Jan 24, 2025
9.8
CRITICALCVSS 3.1
EPSS 0.75%
Description
LibVNCServer 0.9.12 release and earlier contains heap buffer overflow vulnerability within the HandleCursorShape() function in libvncclient/cursor.c. An attacker sends cursor shapes with specially crafted dimensions, which can result in remote code execution.
Affected products
-
- Version -StatusaffectedConstraints<=0.9.12
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
|---|---|---|---|---|---|---|---|---|---|
| LibVNC | LibVNCServer | unaffected |
|
No data.
No data.
Red Hat Enterprise Linux 7
libvncserver-0:0.9.9-14.el7_7
Fixed · RHSA-2020:0913
Red Hat Enterprise Linux 8
libvncserver-0:0.9.11-9.el8_1.2
Fixed · RHSA-2020:0920
Red Hat Enterprise Linux 8.0 Update Services for SAP Solutions
libvncserver-0:0.9.11-9.el8_0.2
Fixed · RHSA-2020:0921
Red Hat Enterprise Linux 6
libvncserver
Out of support scope
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 7 | libvncserver-0:0.9.9-14.el7_7 | Fixed | RHSA-2020:0913 |
| Red Hat Enterprise Linux 8 | libvncserver-0:0.9.11-9.el8_1.2 | Fixed | RHSA-2020:0920 |
| Red Hat Enterprise Linux 8.0 Update Services for SAP Solutions | libvncserver-0:0.9.11-9.el8_0.2 | Fixed | RHSA-2020:0921 |
| Red Hat Enterprise Linux 6 | libvncserver | Out of support scope | n/a |
No package ranges for this CVE.
Remediation
Vendor solution
Update LibVNCServer to the commit with hash 54220248886b5001fbbb9fa73c4e1a2cb9413fed or newer.
Red Hat mitigation
Libvncserver should not be used to connect to untrusted server.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
1 other source (Red Hat) ▾
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
No CVSS v3.0 score for this CVE.
No CVSS v2.0 score for this CVE.
This CVE is not in the KEV list.
CISA SSVC (Vulnrichment)
Stakeholder-Specific Vulnerability Categorization from CISA ADP.
Exploitation
NoneAutomatable
NoTechnical Impact
TotalDecision
n/aAssessed Jan 24, 2025 · SSVC 2.0.3
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 3, 2026.
Score over time
2025–2026- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (6 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 3, 2026 | 0.75% (0.00746) | 53.22th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.71% (0.00713) | 48.63th | v5 (v2026.06.15) |
| Mar 4, 2026 | 4.33% (0.04329) | 88.70th | v4 (v2025.03.14) |
| Jul 11, 2025 | 1.34% (0.01341) | 79.14th | v4 (v2025.03.14) |
| Mar 17, 2025 | 0.18% (0.00184) | 37.92th | v4 (v2025.03.14) |
| Jan 25, 2025 | 0.04% (0.00043) | 11.43th | v3 (v2023.03.01) |
References (5)
- https://access.redhat.com/security/cve/CVE-2019-15690 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1811948 Issue Tracking
- https://ics-cert.kaspersky.com/vulnerabilities/klcert-20-009-remote-code-execution-on-libvnc-version-prior-to-0-9-12/ third-party-advisory
- https://nvd.nist.gov/vuln/detail/CVE-2019-15690
- https://www.cve.org/CVERecord?id=CVE-2019-15690
Change history (0)
No recorded changes yet.