CVE-2021-3592 Information disclosure in QEMU

What is CVE-2021-3592?

CVE-2021-3592 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 bootp_input() function and could occur while processing a udp packet that is smaller than the size of the 'bootp_t' structure. A malicious guest could use this flaw to leak 10 bytes of uninitialized heap memory from the host. 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-2021-3592?

It affects 4 products.

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

How do I fix CVE-2021-3592?

Upgrade to a fixed version.

Is CVE-2021-3592 being exploited?

There is no known exploitation of CVE-2021-3592 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-2021-3592, GHSA-xrpp-vwp4-q9hp, UBUNTU-CVE-2021-3592.