CVE-2018-1000518 websockets is vulnerable to denial of service by memory exhaustion
Attackers can cause denial of service via memory exhaustion by sending crafted compressed frames to websockets servers or clients.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2018-1000518?
CVE-2018-1000518 is a high-severity denial of service vulnerability in n/a, published on 26 Jun 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
aaugustin websockets version 4 contains a CWE-409: Improper Handling of Highly Compressed Data (Data Amplification) vulnerability in Servers and clients, unless configured with compression=None that can result in Denial of Service by memory exhaustion. This attack appear to be exploitable via Sending a specially crafted frame on an established connection. This vulnerability appears to have been fixed in 5.
Weakness: CWE-400
Which versions are affected by CVE-2018-1000518?
3 open source packages ship an affected version, including websockets. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
websockets PyPI | All versions | 5.0 |
websockets PyPI | From 4.0 | 5.0 |
websockets PyPI | From 4.0 | 5.0 |
Linux distribution packages (3)
python-websockets openSUSE:Tumbleweed | All versions | 12.0-2.6 |
python-websockets openSUSE:Tumbleweed | All versions | 16.0-2.1 |
python-websockets openSUSE:Tumbleweed | All versions | 9.1-2.1 |
Products include Websockets Project Websockets.
How do I fix CVE-2018-1000518?
Upgrade websockets to 5.0 or later.
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-2018-1000518 being exploited?
There is no known exploitation of CVE-2018-1000518 in the wild and no public exploit code.
Sources
Also known as GHSA-6g87-ff9q-v847, PYSEC-2018-79, openSUSE-SU-2024:11280-1, openSUSE-SU-2024:14166-1, openSUSE-SU-2026:11240-1.