CVE-2020-11077 HTTP Smuggling via Transfer-Encoding Header in Puma
Attackers can smuggle HTTP requests via Transfer-Encoding headers, causing responses to be sent to wrong clients, leading to data leakage.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2020-11077?
CVE-2020-11077 is a medium-severity vulnerability in Debian Debian Linux, published on 22 May 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
In Puma (RubyGem) before 4.3.5 and 3.12.6, a client could smuggle a request through a proxy, causing the proxy to send a response back to another unknown client. If the proxy uses persistent connections and the client adds another request in via HTTP pipelining, the proxy may mistake it as the first request's body. Puma, however, would see it as two requests, and when processing the second request, send back a response that the proxy does not expect. If the proxy has reused the persistent connection to Puma to send another request for a different client, the second response from the first client will be sent to the second client. This is a similar but different vulnerability from CVE-2020-11076. The problem has been fixed in Puma 3.12.6 and Puma 4.3.5.
Weakness: CWE-444
Which versions are affected by CVE-2020-11077?
4 open source packages ship an affected version, including puma. It affects 4 products.
| Package | Affected | Fixed in |
|---|---|---|
puma RubyGems | All versions | 3.12.6 |
puma RubyGems | All versions | 3.12.6 |
puma RubyGems | From 4.0.0 | 4.3.5 |
puma RubyGems | From 4.0.0 | 4.3.5 |
Products include Debian Debian Linux, Fedoraproject Fedora, Opensuse Leap, Puma Puma.
How do I fix CVE-2020-11077?
Upgrade puma to a fixed version for your release line: 3.12.6 or 4.3.5.
Is CVE-2020-11077 being exploited?
There is no known exploitation of CVE-2020-11077 in the wild and no public exploit code.
Other vulnerabilities in Debian Debian Linux
Sources
Also known as DEBIAN-CVE-2020-11077, GHSA-w64w-qqph-5gxm, UBUNTU-CVE-2020-11077.