CVE-2016-0755: Canonical Ubuntu Linux

High severity, CVSS 7.3. EPSS: 9.3% chance of exploitation in the next 30 days.

The ConnectionExists function in lib/url.c in libcurl before 7.47.0 does not properly re-use NTLM-authenticated proxy connections, which might allow remote attackers to authenticate as other users via a request, a similar issue to CVE-2014-0015.

Affected products

• Canonical Ubuntu Linux: version 12.04 only; version 14.04 only; version 15.04 only; version 15.10 only
• Debian Debian Linux: version 7.0 only
• Haxx Curl: up to and including 7.46.0

Published 2016-01-29. Last modified 2026-06-17.