CVE-2016-2047

Severity: medium (CVSS 5.9 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 3.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2016-01-27 · updated 2026-06-17
Weakness: CWE-254

Description

The ssl_verify_server_cert function in sql-common/client.c in MariaDB before 5.5.47, 10.0.x before 10.0.23, and 10.1.x before 10.1.10; Oracle MySQL 5.5.48 and earlier, 5.6.29 and earlier, and 5.7.11 and earlier; and Percona Server do not properly verify that the server hostname matches a domain name in the subject's Common Name (CN) or subjectAltName field of the X.509 certificate, which allows man-in-the-middle attackers to spoof SSL servers via a "/CN=" string in a field in a certificate, as demonstrated by "/OU=/CN=bar.com/CN=foo.com."

Affected products

Canonical Ubuntu Linux: 12.04, 14.04, 15.10, 16.04
Debian Linux: 8.0, 9.0
MariaDB: from 5.5.20 before 5.5.47; from 10.0.0 before 10.0.23; from 10.1.0 before 10.1.10 — fixed in 10.0.23, 10.1.10, 5.5.47
openSUSE Leap: 42.1
Oracle Corporation Oracle Linux: 7
MySQL Server: from 5.5.0 through 5.5.48; from 5.6.0 through 5.6.29; from 5.7.0 through 5.7.11
Red Hat Enterprise Linux: 6.0, 7.0

How to fix

Upgrade to a fixed version: MariaDB 10.0.23, 10.1.10, 5.5.47. Check the vendor advisory for mitigations.

References

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