CVE-2021-3773 Information disclosure in kernel

What is CVE-2021-3773?

CVE-2021-3773 is a critical vulnerability in Fedoraproject Fedora, published on 16 Feb 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A flaw in netfilter could allow a network-connected attacker to infer openvpn connection endpoint information for further use in traditional network attacks.

Weakness: CWE-200

Which versions are affected by CVE-2021-3773?

It affects 6 products.

Products include Fedoraproject Fedora, Linux kernel, Oracle Communications Cloud Native Core Binding Support Function, Oracle Communications Cloud Native Core Network Exposure Function, Oracle Communications Cloud Native Core Policy, Redhat Enterprise Linux.

How do I fix CVE-2021-3773?

Apply the vendor's patch.

Is CVE-2021-3773 being exploited?

There is no known exploitation of CVE-2021-3773 in the wild and no public exploit code.

Public exploit code: 1 proofs of concept on GitHub.

Other vulnerabilities in Fedoraproject Fedora

• CVE-2024-4577 PHP-CGI OS Command Injection Exploited Critical 9.8
• CVE-2021-39226 Grafana Authentication Bypass Exploited Critical 9.8
• CVE-2019-5544 VMware ESXi and Horizon DaaS OpenSLP Heap-Based Buffer Overflow Exploited Critical 9.8
• 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 GHSA-3xjv-m925-6jcj, ROOT-OS-UBUNTU-2204-CVE-2021-3773, UBUNTU-CVE-2021-3773.