QEMU VNC ui/vnc-clipboard.c inflate_buffer denial of service

CVSS Meta Temp Score
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CTI Interest Score
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5.5$0-$5k0.00

Summaryinfo

A vulnerability has been found in QEMU and classified as problematic. This affects the function inflate_buffer of the file ui/vnc-clipboard.c of the component VNC. The manipulation leads to denial of service. This vulnerability is traded as CVE-2023-3255. There is no exploit available. Applying a patch is the recommended action to fix this issue.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in QEMU (Virtualization Software) (the affected version unknown). This issue affects the function inflate_buffer of the file ui/vnc-clipboard.c of the component VNC. The manipulation with an unknown input leads to a denial of service vulnerability. Using CWE to declare the problem leads to CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. Impacted is availability. The summary by CVE is:

A flaw was found in the QEMU built-in VNC server while processing ClientCutText messages. A wrong exit condition may lead to an infinite loop when inflating an attacker controlled zlib buffer in the `inflate_buffer` function. This could allow a remote authenticated client who is able to send a clipboard to the VNC server to trigger a denial of service.

The weakness was shared 07/04/2023. The advisory is shared at bugzilla.redhat.com. The identification of this vulnerability is CVE-2023-3255 since 06/14/2023. 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.

Applying a patch is able to eliminate this problem. The bugfix is ready for download at lists.nongnu.org.

The vulnerability is also documented in the databases at Tenable (209571) and EUVD (EUVD-2023-43931). 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: 5.5
VulDB Meta Temp Score: 5.5

VulDB Base Score: 3.5
VulDB Temp Score: 3.4
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔍

CNA Base Score: 6.5
CNA Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Denial of service
CWE: 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: Patch
Status: 🔍

0-Day Time: 🔍

Patch: lists.nongnu.org

Timelineinfo

06/14/2023 🔍
07/04/2023 +20 days 🔍
07/04/2023 +0 days 🔍
08/02/2025 +760 days 🔍

Sourcesinfo

Product: qemu.org

Advisory: bugzilla.redhat.com
Status: Confirmed

CVE: CVE-2023-3255 (🔍)
GCVE (CVE): GCVE-0-2023-3255
GCVE (VulDB): GCVE-100-232949
EUVD: 🔍

Entryinfo

Created: 07/04/2023 15:01
Updated: 08/02/2025 21:31
Changes: 07/04/2023 15:01 (40), 09/14/2024 00:15 (37), 10/25/2024 06:28 (2), 08/02/2025 21:31 (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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