CVE-2019-9513 Some HTTP/2 implementations are vulnerable to resource loops, potentially leading to a denial of service
Attackers can cause excessive CPU consumption and denial of service by shuffling HTTP/2 stream priorities, affecting server software implementations.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2019-9513?
CVE-2019-9513 is a high-severity denial of service vulnerability in Apache Traffic Server, published on 13 Aug 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Some HTTP/2 implementations are vulnerable to resource loops, potentially leading to a denial of service. The attacker creates multiple request streams and continually shuffles the priority of the streams in a way that causes substantial churn to the priority tree. This can consume excess CPU.
Weakness: CWE-400
Which versions are affected by CVE-2019-9513?
It affects 20 products.
Products include Apache Traffic Server, Apple Swiftnio, Canonical Ubuntu Linux, Debian Debian Linux, F5 Nginx, Fedoraproject Fedora and 14 more.
How do I fix CVE-2019-9513?
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-2019-9513 being exploited?
There is no known exploitation of CVE-2019-9513 in the wild and no public exploit code.
Other vulnerabilities in Apache Traffic Server
Sources
Also known as ALPINE-CVE-2019-9513, CLEANSTART-2024-ZU11718, CLEANSTART-2026-XJ71643, CVE-2019-14989, DEBIAN-CVE-2019-9513, GHSA-3p35-64mh-v96v and 1 more.