CVE-2018-10548 : Security Advisory and Response

A vulnerability has been found in versions of PHP prior to 5.6.36, 7.0.x before 7.0.30, 7.1.x before 7.1.17, and 7.2.x prior to 7.2.5. This vulnerability in ext/ldap/ldap.c could be exploited by remote LDAP servers, leading to a denial of service due to mishandling of the return value from ldap_get_dn, resulting in a NULL pointer dereference and application crash.

Understanding CVE-2018-10548

This CVE entry describes a vulnerability in PHP versions that could allow remote LDAP servers to cause a denial of service.

What is CVE-2018-10548?

CVE-2018-10548 is a vulnerability in PHP versions prior to 5.6.36, 7.0.x before 7.0.30, 7.1.x before 7.1.17, and 7.2.x prior to 7.2.5, specifically in ext/ldap/ldap.c, which could be exploited by remote LDAP servers.

The Impact of CVE-2018-10548

The vulnerability could lead to a denial of service due to mishandling of the return value from ldap_get_dn, resulting in a NULL pointer dereference and application crash.

Technical Details of CVE-2018-10548

This section provides more technical insights into the CVE.

Vulnerability Description

The issue in ext/ldap/ldap.c allows remote LDAP servers to cause a denial of service due to mishandling of the ldap_get_dn return value.

Affected Systems and Versions

PHP versions prior to 5.6.36
PHP 7.0.x before 7.0.30
PHP 7.1.x before 7.1.17
PHP 7.2.x prior to 7.2.5

Exploitation Mechanism

The vulnerability can be exploited by remote LDAP servers, leveraging the mishandling of the return value from ldap_get_dn.

Mitigation and Prevention

Protecting systems from CVE-2018-10548 is crucial to maintaining security.

Immediate Steps to Take

Update PHP to versions 5.6.36, 7.0.30, 7.1.17, or 7.2.5 or later to mitigate the vulnerability.
Monitor for any unusual LDAP server activities.

Long-Term Security Practices

Regularly update PHP and other software to the latest versions to patch known vulnerabilities.
Implement network security measures to restrict access to critical services.

Patching and Updates

Apply patches provided by PHP to address the vulnerability.