CVE-2018-16844 Denial of service in nginx

What is CVE-2018-16844?

CVE-2018-16844 is a medium-severity denial of service vulnerability in Apple Xcode, published on 7 Nov 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

nginx before versions 1.15.6 and 1.14.1 has a vulnerability in the implementation of HTTP/2 that can allow for excessive CPU usage. This issue affects nginx compiled with the ngx_http_v2_module (not compiled by default) if the 'http2' option of the 'listen' directive is used in a configuration file.

Weakness: CWE-400

Which versions are affected by CVE-2018-16844?

It affects 4 products.

Products include Apple Xcode, Canonical Ubuntu Linux, Debian Debian Linux, F5 Nginx.

How do I fix CVE-2018-16844?

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-2018-16844 being exploited?

There is no known exploitation of CVE-2018-16844 in the wild and no public exploit code.

Other vulnerabilities in Apple Xcode

• CVE-2025-48384 Git Link Following Exploited High 8.1
• CVE-2014-9390 JGit Improper Input Validation vulnerability Critical 9.8
• CVE-2019-14379 Deserialization of untrusted data in FasterXML jackson-databind Critical 9.8
• CVE-2018-4164 An issue was discovered in certain Apple products. Critical 9.8
• CVE-2016-0746 Use after free in n/a Critical 9.8

All Apple Xcode vulnerabilities

Sources

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

Also known as ALPINE-CVE-2018-16844, CLEANSTART-2026-TP31533, DEBIAN-CVE-2018-16844, GHSA-4576-cf38-77f2, UBUNTU-CVE-2018-16844.