What’s Vulnerable › Vulnerabilities

CVE-2020-15136: Improper authentication in etcd

• Severity: medium (CVSS 6.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.6% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2020-08-06 · updated 2026-06-17
• Weakness: CWE-287

Description

In ectd before versions 3.4.10 and 3.3.23, gateway TLS authentication is only applied to endpoints detected in DNS SRV records. When starting a gateway, TLS authentication will only be attempted on endpoints identified in DNS SRV records for a given domain, which occurs in the discoverEndpoints function. No authentication is performed against endpoints provided in the --endpoints flag. This has been fixed in versions 3.4.10 and 3.3.23 with improved documentation and deprecation of the functionality.

Affected products

• Fedoraproject Fedora: 32
• RedHat Etcd: from 3.3.0 before 3.3.23; from 3.4.0 before 3.4.10 — fixed in 3.3.23, 3.4.10

How to fix

Upgrade to a fixed version: RedHat Etcd 3.3.23, 3.4.10. Check the vendor advisory for mitigations.

References

• https://github.com/etcd-io/etcd/blob/master/Documentation/op-guide/gateway.md
• https://github.com/etcd-io/etcd/security/advisories/GHSA-wr2v-9rpq-c35q
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L6B6R43Y7M3DCHWK3L3UVGE2K6WWECMP/
• https://github.com/etcd-io/etcd/blob/master/Documentation/op-guide/gateway.md
• https://github.com/etcd-io/etcd/security/advisories/GHSA-wr2v-9rpq-c35q
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L6B6R43Y7M3DCHWK3L3UVGE2K6WWECMP/

Get alerted when CVE-2020-15136 or the next vulnerability affects your stack