CVE-2018-11796 Explained : Impact and Mitigation

In the Apache Tika 1.19 release (CVE-2018-11761), a vulnerability exists that allows for entity expansion beyond the set limit during XML parsing, potentially leading to a denial of service attack. This vulnerability affects Apache Tika versions 0.1 to 1.19.

Understanding CVE-2018-11796

Apache Tika vulnerability impacting versions 0.1 to 1.19.

What is CVE-2018-11796?

CVE-2018-11796 is a security vulnerability in Apache Tika versions 0.1 to 1.19 that allows for entity expansion beyond the intended limit during XML parsing, creating a potential denial of service risk.

The Impact of CVE-2018-11796

The vulnerability in Apache Tika versions 0.1 to 1.19 can be exploited to trigger a denial of service attack, potentially disrupting services and causing system unavailability.

Technical Details of CVE-2018-11796

Details of the vulnerability in Apache Tika versions 0.1 to 1.19.

Vulnerability Description

In Apache Tika 1.19, a limit on entity expansion was introduced for XML parsing.
Reusing SAXParsers and calling the reset() method after each parse removes the SecurityManager, allowing entity expansion limits to be bypassed.

Affected Systems and Versions

Product: Apache Tika
Vendor: Apache Software Foundation
Versions Affected: Apache Tika 0.1 to 1.19

Exploitation Mechanism

Attackers can exploit the vulnerability by triggering entity expansions beyond the defined limit during XML parsing, potentially leading to a denial of service attack.

Mitigation and Prevention

Protective measures to address CVE-2018-11796.

Immediate Steps to Take

Upgrade to Apache Tika version 1.19.1 or any subsequent release to mitigate the vulnerability.

Long-Term Security Practices

Regularly update software and apply security patches to prevent exploitation of known vulnerabilities.

Patching and Updates

Stay informed about security advisories and promptly apply patches to secure systems against potential threats.