CVE-2016-4800 Jetty contains an alias issue that could allow unauthenticated remote code execution due to specially crafted request

What is CVE-2016-4800?

CVE-2016-4800 is a critical path traversal vulnerability in Eclipse Jetty, published on 13 Apr 2017. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

The path normalization mechanism in PathResource class in Eclipse Jetty 9.3.x before 9.3.9 on Windows allows remote attackers to bypass protected resource restrictions and other security constraints via a URL with certain escaped characters, related to backslashes.

Weakness: CWE-284

Which versions are affected by CVE-2016-4800?

2 open source packages ship an affected version, including org.eclipse.jetty:jetty-server. It affects 1 product.

Products include Eclipse Jetty.

How do I fix CVE-2016-4800?

Upgrade org.eclipse.jetty:jetty-server to 9.3.9 or later.

Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.

Is CVE-2016-4800 being exploited?

There is no known exploitation of CVE-2016-4800 in the wild and no public exploit code.

Other vulnerabilities in Eclipse Jetty

• CVE-2019-17638 Operation on a Resource after Expiration or Release in Jetty Server Critical 9.4
• CVE-2018-12538 Access and integrity issue within Eclipse Jetty High 8.8
• CVE-2026-10050 Digest authentication lossy encoding High 8.7
• CVE-2025-5115 MadeYouReset HTTP/2 vulnerability High 7.7
• CVE-2024-7708 Eclipse Jetty: DoS attack triggering OutOfMemory with 100-Continue requests High 7.5

All Eclipse Jetty vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-872g-2h8h-362q.