CVE-2015-4734

What it actually does

Unspecified flaw in JGSS component allows remote unauthenticated attackers to obtain partial confidential information from affected Oracle Java SE installations.

Why it matters to the business

Legacy systems running vulnerable Java versions risk exposure of sensitive data to remote attackers, potentially leading to compliance issues or data leaks if unpatched instances remain in use after many years.

How an attack unfolds

An attacker targets a remote service using vulnerable Java SE JGSS functionality by sending specially crafted network requests that trigger the unspecified information disclosure vector, allowing capture of confidential data without authentication.

How to fix it

Update affected Java SE installations beyond the vulnerable releases (6u101, 7u85, 8u60, Embedded 8u51). For the listed package, apply flashplugin-nonfree (Ubuntu:14.04:LTS) fixed in 25.0.0.171ubuntu0.14.04.1.

How to confirm the fix worked

Verify Java version strings no longer match vulnerable releases; test network services for absence of the JGSS information disclosure behavior using updated builds.

Typical attack path

1. Scan for exposed services running affected Java SE versions
2. Craft and send malicious JGSS protocol requests over the network
3. Capture and analyze responses to extract leaked confidential information

How to detect it

Review application and network logs for unusual JGSS-related traffic patterns or unexpected data exposure from Java processes; check historical access logs around the time of any suspected interaction with vulnerable versions.

What your security team should do

• Prioritize inventory of all Java SE deployments given the 4005+ days since publication
• Apply available updates immediately on any remaining legacy instances
• Monitor EPSS trend for any future increase in exploitation likelihood