#VU64828 Improper Authentication in etcd - CVE-2018-16886

Vulnerability identifier: #VU64828

Vulnerability risk: Low

CVSSv4.0: 4.9 [CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2018-16886

CWE-ID: CWE-287

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
etcd
Server applications / Database software

Vendor: CoreOS

Description

The vulnerability allows a remote user to bypass authentication process.

The vulnerability exists due to an improper authentication issue when role-based access control (RBAC) is used and client-cert-auth is enabled. A remote user can authenticate as user with any valid (trusted) client certificate in a REST API request to the gRPC-gateway.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

etcd: 3.2.0 - 3.3.10

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External links
https://www.securityfocus.com/bid/106540
https://access.redhat.com/errata/RHSA-2019:0237
https://access.redhat.com/errata/RHSA-2019:1352
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-16886
https://github.com/etcd-io/etcd/blob/1eee465a43720d713bb69f7b7f5e120135fdb1ac/CHANGELOG-3.2.md#security-authentication
https://github.com/etcd-io/etcd/blob/1eee465a43720d713bb69f7b7f5e120135fdb1ac/CHANGELOG-3.3.md#security-authentication

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.