CVE-2015-4334: Symantec Proxysg Firmware

Medium severity, CVSS 5.0. EPSS: 3.3% chance of exploitation in the next 30 days.

The default configuration of SGOS in Blue Coat ProxySG before 6.2.16.5, 6.5 before 6.5.7.1, and 6.6 before 6.6.2.1 forwards authentication challenges from upstream origin content servers (OCS) when used in an explicit proxy deployment, which makes it easier for remote attackers to obtain sensitive information via a 407 (aka Proxy Authentication Required) HTTP status code, as demonstrated when using NTLM authentication.

Affected products

• Symantec Proxysg Firmware: from 6.2, up to and including 6.2.16.4; from 6.5, up to and including 6.5.7.0; from 6.6, up to and including 6.6.2.0

Published 2015-12-07. Last modified 2026-06-17.