CVE-2019-9900
HIGH severity · CVSS 8.3 · Injection
8.3CVSS HIGH
Summary
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.
Impact & exploitability
Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
Confidentiality impactLow
Integrity impactLow
Availability impactLow
Exploit probability (EPSS)4%
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L
Affected products we track (1)
Recommendation
Apply the vendor fix promptly. Open any affected product above for its exact safe version.
Additional information
- NVD record
- https://www.envoyproxy.io/docs/envoy/v1.9.1/intro/version_historyAdvisory
- https://github.com/envoyproxy/envoy/security/advisories/GHSA-x74r-f4mw-c32hAdvisory
- https://access.redhat.com/errata/RHSA-2019:0741Advisory
- https://groups.google.com/forum/#%21topic/envoy-announce/VoHfnDqZiAM
- https://github.com/envoyproxy/envoy/issues/6434Advisory