CVE-2018-14404 : Exploit Details and Defense Strategies

A vulnerability in the libxml2 library up to version 2.9.8 can lead to a denial of service attack due to a NULL pointer dereference in the xpath.c:xmlXPathCompOpEval() function.

Understanding CVE-2018-14404

This CVE involves a vulnerability in the libxml2 library that can be exploited to cause a denial of service attack.

What is CVE-2018-14404?

The xpath.c:xmlXPathCompOpEval() function in libxml2 up to version 2.9.8 is susceptible to a NULL pointer dereference when processing an invalid XPath expression under specific conditions, potentially leading to a crash in applications using untrusted XSL format inputs.

The Impact of CVE-2018-14404

The vulnerability can be exploited to trigger a denial of service attack, causing affected applications to crash, potentially disrupting their functionality.

Technical Details of CVE-2018-14404

This section provides more technical insights into the CVE.

Vulnerability Description

The vulnerability exists in the xpath.c:xmlXPathCompOpEval() function of libxml2 through version 2.9.8, allowing for a NULL pointer dereference when processing invalid XPath expressions under certain conditions.

Affected Systems and Versions

Product: N/A
Vendor: N/A
Versions affected: Up to version 2.9.8

Exploitation Mechanism

The vulnerability is triggered when parsing an invalid XPath expression under the XPATH_OP_AND or XPATH_OP_OR condition, potentially leading to a denial of service attack.

Mitigation and Prevention

Protecting systems from CVE-2018-14404 requires specific actions.

Immediate Steps to Take

Update libxml2 to a patched version that addresses the vulnerability.
Avoid processing untrusted XSL format inputs until the library is updated.

Long-Term Security Practices

Regularly update software libraries and dependencies to mitigate known vulnerabilities.
Implement input validation mechanisms to prevent the exploitation of similar vulnerabilities.

Patching and Updates

Apply patches provided by the libxml2 library to fix the vulnerability and enhance system security.