CVE-2020-35498 Denial of service in openvswitch

What is CVE-2020-35498?

CVE-2020-35498 is a high-severity denial of service vulnerability in Debian Debian Linux, published on 11 Feb 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A vulnerability was found in openvswitch. A limitation in the implementation of userspace packet parsing can allow a malicious user to send a specially crafted packet causing the resulting megaflow in the kernel to be too wide, potentially causing a denial of service. The highest threat from this vulnerability is to system availability.

Weakness: CWE-400

Which versions are affected by CVE-2020-35498?

It affects 3 products.

Products include Debian Debian Linux, Fedoraproject Fedora, Openvswitch Openvswitch.

How do I fix CVE-2020-35498?

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-2020-35498 being exploited?

There is no known exploitation of CVE-2020-35498 in the wild and no public exploit code.

Public exploit code: 1 proofs of concept on GitHub.

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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-2020-35498, DSA-4852-1, GHSA-9978-p96m-85pj, SUSE-SU-2021:0436-1, SUSE-SU-2021:0439-1, SUSE-SU-2021:0440-1 and 7 more.