High severity · published Apr 25, 2019
CVE-2019-9900
When parsing HTTP/1.x header values, Envoy 1.9.0 and before does not reject embedded zero characters (NUL, ASCII 0x0)
8.3
CVSS
3.7%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
Low
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)3.7% · higher than 90% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
EN
Envoy · Envoyproxy
through 1.9.0 · source: NVD
OS
Openshift Service Mesh · Redhat
All versions, or not specified · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2019-9900
CVE.org
https://www.cve.org/CVERecord?id=CVE-2019-9900
Third Party Advisory
https://access.redhat.com/errata/RHSA-2019:0741
Exploit
https://github.com/envoyproxy/envoy/issues/6434
Exploit
https://github.com/envoyproxy/envoy/security/advisories/GHSA-x74r-f4mw-c32h
groups.google.com
https://groups.google.com/forum/#%21topic/envoy-announce/VoHfnDqZiAM
Release Notes
https://www.envoyproxy.io/docs/envoy/v1.9.1/intro/version_history
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