CVE-2015-0799: Canonical Ubuntu Linux

Medium severity, CVSS 4.3. EPSS: 1.2% chance of exploitation in the next 30 days.

The HTTP Alternative Services feature in Mozilla Firefox before 37.0.1 allows man-in-the-middle attackers to bypass an intended X.509 certificate-verification step for an SSL server by specifying that server in the uri-host field of an Alt-Svc HTTP/2 response header.

Affected products

• Canonical Ubuntu Linux: version 12.04 only; version 14.04 only; version 14.10 only
• Mozilla Firefox: up to and including 37.0
• Opensuse Opensuse: version 13.1 only; version 13.2 only

Published 2015-04-08. Last modified 2026-06-17.