CVE-2021-3466 Memory corruption in libmicrohttpd

What is CVE-2021-3466?

CVE-2021-3466 is a critical memory corruption vulnerability in Fedoraproject Fedora, published on 25 Mar 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A flaw was found in libmicrohttpd. A missing bounds check in the post_process_urlencoded function leads to a buffer overflow, allowing a remote attacker to write arbitrary data in an application that uses libmicrohttpd. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability. Only version 0.9.70 is vulnerable.

Weakness: CWE-120

Which versions are affected by CVE-2021-3466?

It affects 3 products.

Products include Fedoraproject Fedora, Gnu Libmicrohttpd, Redhat Enterprise Linux.

How do I fix CVE-2021-3466?

Upgrade to a fixed version.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2021-3466 being exploited?

There is no known exploitation of CVE-2021-3466 in the wild and no public exploit code.

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 DEBIAN-CVE-2021-3466, ECHO-7632-c491-0f24, GHSA-vjm5-89cg-7hj8.