CVE-2017-11164 : Exploit Details and Defense Strategies

CVE-2017-11164 is a vulnerability in PCRE 8.41 that can lead to stack exhaustion or uncontrolled recursion when processing specially crafted regular expressions.

Understanding CVE-2017-11164

The vulnerability in PCRE 8.41 can be exploited through a feature called OP_KETRMAX, potentially causing severe consequences.

What is CVE-2017-11164?

The match function in pcre_exec.c of PCRE 8.41 contains a feature known as OP_KETRMAX, which, when processing a maliciously crafted regular expression, can trigger stack exhaustion or uncontrolled recursion, leading to a denial of service condition.

The Impact of CVE-2017-11164

This vulnerability can be exploited by an attacker to crash applications or execute arbitrary code by sending a specially designed regular expression.

Technical Details of CVE-2017-11164

The technical aspects of the CVE-2017-11164 vulnerability are as follows:

Vulnerability Description

The issue lies in the match function of PCRE 8.41, specifically in the OP_KETRMAX feature, which can be abused to exhaust the stack or cause uncontrolled recursion.

Affected Systems and Versions

Vendor: n/a
Product: n/a
Versions: All versions of PCRE 8.41 are affected.

Exploitation Mechanism

Attackers can exploit this vulnerability by crafting a malicious regular expression that triggers the OP_KETRMAX feature, leading to stack exhaustion or uncontrolled recursion.

Mitigation and Prevention

To address CVE-2017-11164, consider the following mitigation strategies:

Immediate Steps to Take

Apply vendor patches or updates promptly.
Implement input validation to prevent malicious regular expressions.

Long-Term Security Practices

Regularly update and patch software to mitigate known vulnerabilities.
Monitor security mailing lists and advisories for updates on vulnerabilities.

Patching and Updates

Ensure that PCRE is updated to a non-vulnerable version.
Stay informed about security updates and apply them as soon as they are available.