CVE-2018-16868: GNU Gnutls

Medium severity, CVSS 5.6. EPSS: 0.6% chance of exploitation in the next 30 days.

A Bleichenbacher type side-channel based padding oracle attack was found in the way gnutls handles verification of RSA decrypted PKCS#1 v1.5 data. An attacker who is able to run process on the same physical core as the victim process, could use this to extract plaintext or in some cases downgrade any TLS connections to a vulnerable server.

Affected products

• GNU Gnutls: up to and including 3.6.4

Published 2018-12-03. Last modified 2026-06-17.