Qemu: vnc: null pointer dereference in qemu_clipboard_request()

Summary

CVECVE-2023-6683
StatePUBLISHED
Assignerredhat
Source PriorityCVE Program / NVD first with legacy fallback
Published2024-01-12 19:15:11 UTC
Updated2026-11-05 12:17:38 UTC
DescriptionA flaw was found in the QEMU built-in VNC server while processing ClientCutText messages. The qemu_clipboard_request() function can be reached before vnc_server_cut_text_caps() was called and had the chance to initialize the clipboard peer, leading to a NULL pointer dereference. This could allow a malicious authenticated VNC client to crash QEMU and trigger a denial of service.

Risk And Classification

Primary CVSS: v3.1 6.5 MEDIUM from [email protected]

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Problem Types: CWE-476 | CWE-476 NULL Pointer Dereference


VersionSourceTypeScoreSeverityVector
3.1[email protected]Primary6.5MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
3.1[email protected]Secondary6.5MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
3.1CNACVSS6.5MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS v3.1 Breakdown

Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Qemu Qemu All All All All
Operating System Redhat Enterprise Linux 8.0 All All All
Operating System Redhat Enterprise Linux 9.0 All All All

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Red Hat Red Hat Enterprise Linux 8 unaffected 8100020240314161907.e155f54d * rpm Not specified
CNA Red Hat Red Hat Enterprise Linux 8 unaffected 8100020240314161907.e155f54d * rpm Not specified
CNA Red Hat Red Hat Enterprise Linux 9 unaffected 17:8.2.0-11.el9_4 * rpm Not specified
CNA Red Hat Red Hat Enterprise Linux 6 Not specified Not specified
CNA Red Hat Red Hat Enterprise Linux 7 Not specified Not specified
CNA Red Hat Red Hat Enterprise Linux 7 Not specified Not specified
CNA Red Hat Red Hat Enterprise Linux 8 Advanced Virtualization Not specified Not specified

References

ReferenceSourceLinkTags
bugzilla.redhat.com/show_bug.cgi af854a3a-2127-422b-91ae-364da2661108 bugzilla.redhat.com Issue Tracking, Patch
access.redhat.com/security/cve/CVE-2023-6683 af854a3a-2127-422b-91ae-364da2661108 access.redhat.com Third Party Advisory
security.netapp.com/advisory/ntap-20240223-0001 af854a3a-2127-422b-91ae-364da2661108 security.netapp.com Third Party Advisory
access.redhat.com/errata/RHSA-2024:2135 af854a3a-2127-422b-91ae-364da2661108 access.redhat.com Third Party Advisory
access.redhat.com/errata/RHSA-2024:2962 af854a3a-2127-422b-91ae-364da2661108 access.redhat.com Third Party Advisory
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Vendor Comments And Credit

Discovery Credit

CNA: Red Hat would like to thank Fiona Ebner (Proxmox) and Markus Frank (Proxmox) for reporting this issue. (en)

Additional Advisory Data

SourceTimeEvent
CNA2023-12-11T00:00:00.000ZReported to Red Hat.
CNA2024-01-12T00:00:00.000ZMade public.

Workarounds

CNA: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.

Legacy QID Mappings

  • 161478 Oracle Enterprise Linux Security Update for virt:kvm_utils3 (ELSA-2024-12276)

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