CVE-2018-8970: OpenBSD Libressl

High severity, CVSS 7.4. EPSS: 1% chance of exploitation in the next 30 days.

The int_x509_param_set_hosts function in lib/libcrypto/x509/x509_vpm.c in LibreSSL 2.7.0 before 2.7.1 does not support a certain special case of a zero name length, which causes silent omission of hostname verification, and consequently allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate. NOTE: the LibreSSL documentation indicates that this special case is supported, but the BoringSSL documentation does not.

Affected products

• OpenBSD Libressl: version 2.7.0 only

Published 2018-03-24. Last modified 2026-06-17.