CVE-2021-3594 Information disclosure in QEMU

What is CVE-2021-3594?

CVE-2021-3594 is a low-severity vulnerability in Debian Debian Linux, published on 15 Jun 2021. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

An invalid pointer initialization issue was found in the SLiRP networking implementation of QEMU. The flaw exists in the udp_input() function and could occur while processing a udp packet that is smaller than the size of the 'udphdr' structure. This issue may lead to out-of-bounds read access or indirect host memory disclosure to the guest. The highest threat from this vulnerability is to data confidentiality. This flaw affects libslirp versions prior to 4.6.0.

Weakness: CWE-824

Which versions are affected by CVE-2021-3594?

It affects 4 products.

Products include Debian Debian Linux, Fedoraproject Fedora, Libslirp Project Libslirp, Redhat Enterprise Linux.

How do I fix CVE-2021-3594?

Upgrade to a fixed version.

Is CVE-2021-3594 being exploited?

There is no known exploitation of CVE-2021-3594 in the wild and no public exploit code.

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All Debian Debian Linux vulnerabilities

Sources

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

Also known as DEBIAN-CVE-2021-3594, GHSA-wh9f-45px-j437, UBUNTU-CVE-2021-3594, openSUSE-SU-2024:10628-1.