CVE-2018-17189 Denial of service in Apache HTTP Server

What is CVE-2018-17189?

CVE-2018-17189 is a medium-severity denial of service vulnerability in Apache Http Server, published on 30 Jan 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

In Apache HTTP server versions 2.4.37 and prior, by sending request bodies in a slow loris way to plain resources, the h2 stream for that request unnecessarily occupied a server thread cleaning up that incoming data. This affects only HTTP/2 (mod_http2) connections.

Weakness: CWE-400

Which versions are affected by CVE-2018-17189?

It affects 12 products.

Products include Apache Http Server, Canonical Ubuntu Linux, Debian Debian Linux, Fedoraproject Fedora, Netapp Santricity Cloud Connector, Netapp Storage Automation Store and 6 more.

How do I fix CVE-2018-17189?

Upgrade to a fixed version.

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-2018-17189 being exploited?

There is no known exploitation of CVE-2018-17189 in the wild and no public exploit code.

Other vulnerabilities in Apache Http Server

• CVE-2021-42013 Apache HTTP Server Path Traversal Exploited Critical 9.8
• CVE-2024-38475 Apache HTTP Server Improper Escaping of Output Exploited Critical 9.1
• CVE-2021-40438 Apache HTTP Server-Side Request Forgery (SSRF) Exploited Critical 9.0
• CVE-2019-0211 Apache HTTP Server Privilege Escalation Exploited High 7.8
• CVE-2021-41773 Apache HTTP Server Path Traversal Exploited High 7.5

All Apache Http Server vulnerabilities

Sources

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

Also known as ALPINE-CVE-2018-17189, CLEANSTART-2026-XI76483, DEBIAN-CVE-2018-17189, GHSA-xcwr-pcwv-7gm8, UBUNTU-CVE-2018-17189.