Qemu: vnc: infinite loop in inflate_buffer() leads to denial of service

6.5 CVSS

Vulnerability Description

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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

Red Hat would like to thank Kevin Denis (Synacktiv) for reporting this issue.

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Affected Vendor

Red Hat

View all reports →

Affected Software

Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8 Advanced Virtualization

Vulnerable Versions:

8100020240314161907.e155f54d, 17:8.2.0-11.el9_4