CVE-2019-9900 Security feature bypass in n/a
Attackers can bypass header matching rules in Envoy proxy by embedding NUL characters in HTTP headers, gaining unauthorized access to resources.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2019-9900?
CVE-2019-9900 is a medium-severity vulnerability in Envoyproxy Envoy, published on 25 Apr 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
When parsing HTTP/1.x header values, Envoy 1.9.0 and before does not reject embedded zero characters (NUL, ASCII 0x0). This allows remote attackers crafting header values containing embedded NUL characters to potentially bypass header matching rules, gaining access to unauthorized resources.
Weakness: CWE-74
Which versions are affected by CVE-2019-9900?
It affects 2 products.
Products include Envoyproxy Envoy, Redhat Openshift Service Mesh.
How do I fix CVE-2019-9900?
Upgrade to a fixed version.
Is CVE-2019-9900 being exploited?
There is no known exploitation of CVE-2019-9900 in the wild and no public exploit code.
Other vulnerabilities in Envoyproxy Envoy
Sources
Also known as GHSA-h9r7-c397-3wqr, GHSA-x74r-f4mw-c32h.