CVE-2011-2526 Improper Input Validation in Apache Tomcat

What is CVE-2011-2526?

CVE-2011-2526 is a medium-severity vulnerability in Apache Tomcat, published on 14 Jul 2011. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

Apache Tomcat 5.5.x before 5.5.34, 6.x before 6.0.33, and 7.x before 7.0.19, when sendfile is enabled for the HTTP APR or HTTP NIO connector, does not validate certain request attributes, which allows local users to bypass intended file access restrictions or cause a denial of service (infinite loop or JVM crash) by leveraging an untrusted web application.

Weakness: CWE-20

Which versions are affected by CVE-2011-2526?

6 open source packages ship an affected version, including org.apache.tomcat:tomcat. It affects 1 product.

Products include Apache Tomcat.

How do I fix CVE-2011-2526?

Upgrade org.apache.tomcat:tomcat to a fixed version for your release line: 5.5.34, 6.0.33 or 7.0.19.

Is CVE-2011-2526 being exploited?

There is no known exploitation of CVE-2011-2526 in the wild and no public exploit code.

Other vulnerabilities in Apache Tomcat

• CVE-2025-24813 Apache Tomcat Path Equivalence Exploited Critical 10.0
• CVE-2016-8735 Apache Tomcat Remote Code Execution Exploited Critical 9.8
• CVE-2017-12617 Apache Tomcat Remote Code Execution Exploited High 8.1
• CVE-2017-12615 Apache Tomcat on Windows Remote Code Execution Exploited High 8.1
• CVE-2026-34486 Apache Tomcat Missing Encryption of Sensitive Data Exploited High 7.5

All Apache Tomcat vulnerabilities

Sources

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

Also known as GHSA-9ggm-7897-x4mg.