#VU31125 Security Features in Kubernetes - CVE-2019-9946
Published: April 2, 2019 / Updated: July 17, 2020
Vulnerability identifier: #VU31125
Vulnerability risk: Medium
CVSSv4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2019-9946
CWE-ID: CWE-254
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
Kubernetes
Kubernetes
Software vendor:
Kubernetes
Kubernetes
Description
The vulnerability allows a remote non-authenticated attacker to manipulate data.
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.
Remediation
Install update from vendor's website.
External links
- https://access.redhat.com/errata/RHBA-2019:0862
- https://github.com/containernetworking/plugins/pull/269#issuecomment-477683272
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/FCN66VYB3XS76SYH567SO7N3I254JOCT/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/SGOOWAELGH3F7OXRBPH3HCNZELNLXYTW/
- https://security.netapp.com/advisory/ntap-20190416-0002/