HOMEVULNERABILITIESCVE-2016-9603
MEDIUM

CVE-2016-9603

CWE-122Published: July 27, 2018· Updated: Jun 17, 2026

5.5
CVSS v3.1

Official Description

A heap buffer overflow flaw was found in QEMU's Cirrus CLGD 54xx VGA emulator's VNC display driver support before 2.9; the issue could occur when a VNC client attempted to update its display after a VGA operation is performed by a guest. A privileged user/process inside a guest could use this flaw to crash the QEMU process or, potentially, execute arbitrary code on the host with privileges of the QEMU process.

NVD Source

Technical Analysis

CVE-2016-9603 requires adjacent network access, limiting remote exploitation but still posing risk in shared or local network environments.

Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorAdjacent
Attack ComplexityHigh
Privileges Req.Low
User InteractionNone
ScopeChanged
Impact
ConfidentialityLow
IntegrityLow
AvailabilityLow
CVSS:3.0/AV:A/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:L

Affected Vendors & Products

citrix1 product(s)
xenserver
Debian1 product(s)
debian linux
qemu1 product(s)
qemu
Red Hat6 product(s)
openstackenterprise linux desktopenterprise linux serverenterprise linux server ausenterprise linux server eusenterprise linux workstation
Source: NVD CPE · 24 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
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Official Patches & Advisories

All References (36)

Quick Facts

CVE IDCVE-2016-9603
CVSS Score5.5 / 10
SeverityMEDIUM
WeaknessCWE-122
CISA KEVNo
Affected4 vendor(s)
PublishedJul 27, 2018

Related CVEs (CWE-122)

Recommended Actions

  • Apply vendor patches immediately
  • Monitor CVE-2016-9603 in threat intel feeds
  • Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.