QEMU Built-In VNC Server qemu_clipboard_request null pointer dereference

CVSS Meta Temp Score
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CTI Interest Score
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6.4$0-$5k0.00

Summaryinfo

A vulnerability marked as problematic has been reported in QEMU. The impacted element is the function qemu_clipboard_request of the component Built-In VNC Server. Performing a manipulation results in null pointer dereference. This vulnerability was named CVE-2023-6683. The attack may be initiated remotely. There is no available exploit. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in QEMU (Virtualization Software) (the affected version is unknown). This affects the function qemu_clipboard_request of the component Built-In VNC Server. The manipulation with an unknown input leads to a null pointer dereference vulnerability. CWE is classifying the issue as CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. This is going to have an impact on availability. The summary by CVE is:

A 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.

The weakness was presented 01/12/2024. The advisory is shared at access.redhat.com. This vulnerability is uniquely identified as CVE-2023-6683 since 12/11/2023. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 209571 (Oracle Linux 8 : virt:kvm_utils3 (ELSA-2024-12792)), which helps to determine the existence of the flaw in a target environment.

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (209571) and EUVD (EUVD-2023-58904). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.5
VulDB Meta Temp Score: 6.4

VulDB Base Score: 6.5
VulDB Temp Score: 6.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔍

CNA Base Score: 6.5
CNA Vector (Red Hat, Inc.): 🔍

CVSSv2info

AVACAuCIA
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 209571
Nessus Name: Oracle Linux 8 : virt:kvm_utils3 (ELSA-2024-12792)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

12/11/2023 🔍
01/12/2024 +32 days 🔍
01/12/2024 +0 days 🔍
08/02/2025 +568 days 🔍

Sourcesinfo

Product: qemu.org

Advisory: access.redhat.com
Status: Confirmed

CVE: CVE-2023-6683 (🔍)
GCVE (CVE): GCVE-0-2023-6683
GCVE (VulDB): GCVE-100-250653
EUVD: 🔍

Entryinfo

Created: 01/12/2024 20:49
Updated: 08/02/2025 18:24
Changes: 01/12/2024 20:49 (49), 09/14/2024 06:45 (26), 10/25/2024 05:47 (2), 08/02/2025 18:24 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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