6.5 Medium

A flaw was found in the QEMU built-in VNC server while processing ClientCutText messages.

CVE-2023-3255

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 inflatebuffer 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.

Assessment

CVSS: 6.5 (v3.1)
Severity: Medium
EPSS: 1.89% chance of exploitation in the next 30 days
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 13 September 2023
Last updated: 1 November 2026
Affected: Red Hat
Assigner: redhat

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

At the source

EUVD (ENISA)

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