title: Qemu: vnc: null pointer dereference in qemu_clipboard_request()
description: 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.
problem types: NULL Pointer Dereference
affected:
{
product: qemu
vendor: n/a
defaultStatus: affected
}
{
vendor: Red Hat
product: Red Hat Enterprise Linux 6
collectionURL: https://access.redhat.com/downloads/content/package-browser/
packageName: qemu-kvm
defaultStatus: unaffected
cpes: cpe:/o:redhat:enterprise_linux:6
}
{
vendor: Red Hat
product: Red Hat Enterprise Linux 7
collectionURL: https://access.redhat.com/downloads/content/package-browser/
packageName: qemu-kvm
defaultStatus: unaffected
cpes: cpe:/o:redhat:enterprise_linux:7
}
{
vendor: Red Hat
product: Red Hat Enterprise Linux 7
collectionURL: https://access.redhat.com/downloads/content/package-browser/
packageName: qemu-kvm-ma
defaultStatus: unaffected
cpes: cpe:/o:redhat:enterprise_linux:7
}
{
vendor: Red Hat
product: Red Hat Enterprise Linux 8
collectionURL: https://access.redhat.com/downloads/content/package-browser/
packageName: virt:rhel/qemu-kvm
defaultStatus: affected
cpes: cpe:/o:redhat:enterprise_linux:8
}
{
vendor: Red Hat
product: Red Hat Enterprise Linux 8 Advanced Virtualization
collectionURL: https://access.redhat.com/downloads/content/package-browser/
packageName: virt:av/qemu-kvm
defaultStatus: unaffected
cpes: cpe:/a:redhat:advanced_virtualization:8::el8
}
{
vendor: Red Hat
product: Red Hat Enterprise Linux 9
collectionURL: https://access.redhat.com/downloads/content/package-browser/
packageName: qemu-kvm
defaultStatus: affected
cpes: cpe:/o:redhat:enterprise_linux:9
}
{
product: Fedora
vendor: Fedora
collectionURL: https://packages.fedoraproject.org/
packageName: qemu
defaultStatus: affected
}
metrics:
other: [
content: {'value': 'Moderate', 'namespace': 'https://access.redhat.com/security/updates/classification/'}
type: Red Hat severity rating
]
workarounds: 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.