CVE-2023-3255 Qemu: vnc: infinite loop in inflate_buffer() leads to denial of service

What is CVE-2023-3255?

CVE-2023-3255 is a medium-severity denial of service vulnerability in Fedoraproject Fedora, published on 13 Sep 2023. Any signed-in user can exploit it over the network, with no action from the victim.

Official 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.

Weakness: CWE-835

Which versions are affected by CVE-2023-3255?

It affects 3 products.

Products include Fedoraproject Fedora, Qemu Qemu, Redhat Enterprise Linux.

How do I fix CVE-2023-3255?

Apply the vendor's patch.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2023-3255 being exploited?

There is no known exploitation of CVE-2023-3255 in the wild and no public exploit code.

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• CVE-2024-4947 Google Chromium V8 Type Confusion Exploited Critical 9.6
• CVE-2024-4671 Google Chromium Visuals Use-After-Free Exploited Critical 9.6

All Fedoraproject Fedora vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as AZL-28791, AZL-35169, BELL-CVE-2023-3255, DEBIAN-CVE-2023-3255, GHSA-p5xv-5g6h-qw33, OESA-2023-1785 and 4 more.