Vulnerability in Cncf Portmap

CVE-2019-9946

Cloud Native Computing Foundation (CNCF) CNI (Container Networking Interface) 0.7.4 has a network firewall misconfiguration which affects Kubernetes. The CNI 'portmap' plugin, used to setup HostPorts for CNI, inserts rules at the front of the iptables nat chains; which take precedence over the KUBE- SERVICES chain. Because of this, the HostPort/portmap rule could match incoming traffic even if there were better fitting, more specific service definition rules like NodePorts later in the chain. The issue is fixed in CNI 0.7.5 and Kubernetes 1.11.9, 1.12.7, 1.13.5, and 1.14.0.

EPSS: 0.032 (87.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2019-9946?
CVE-2019-9946 is a high-severity vulnerability in Cncf Portmap, classified under Always-Incorrect Control Flow Implementation. CVSS score: 7.5/10. Published 2019-04-02.
How severe is CVE-2019-9946?
High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2019-9946 known to be exploited?
9 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.