PHP CVE-2019-11046 Buffer Underflow Vulnerability

Description

PHP is prone to a buffer-underflow vulnerability. An attacker can exploit this issue to cause denial-of-service conditions. Due to the nature of this issue, arbitrary code execution may be possible but this has not been confirmed. PHP 7.2.x versions prior to 7.2.26, 7.3.x versions prior to 7.3.13 and version 7.4.0 are vulnerable.

Technologies Affected

• PHP PHP 7.2.0
• PHP PHP 7.2.1
• PHP PHP 7.2.12
• PHP PHP 7.2.13
• PHP PHP 7.2.14
• PHP PHP 7.2.16
• PHP PHP 7.2.17
• PHP PHP 7.2.18
• PHP PHP 7.2.19
• PHP PHP 7.2.2
• PHP PHP 7.2.25
• PHP PHP 7.3.0
• PHP PHP 7.3.1
• PHP PHP 7.3.10
• PHP PHP 7.3.11
• PHP PHP 7.3.12
• PHP PHP 7.3.2
• PHP PHP 7.3.3
• PHP PHP 7.3.4
• PHP PHP 7.3.5
• PHP PHP 7.3.6
• PHP PHP 7.3.7
• PHP PHP 7.3.8
• PHP PHP 7.3.9
• PHP PHP 7.4.0

Recommendations

Deploy network intrusion detection systems to monitor network traffic for malicious activity.
Deploy NIDS to monitor network traffic for signs of anomalous or suspicious activity. This includes but is not limited to requests that include NOP sleds and unexplained incoming and outgoing traffic. This may indicate exploit attempts or activity that results from a successful exploit.

Do not accept or execute files from untrusted or unknown sources.
To limit exposure to these and other latent vulnerabilities, never handle files that originate from unfamiliar or untrusted sources.

Implement multiple redundant layers of security.
As an added precaution, deploy memory-protection schemes (such as nonexecutable stack/heap configuration and randomly mapped memory segments). This may complicate exploits of memory-corruption vulnerabilities.

Run all software as a nonprivileged user with minimal access rights.
To reduce the impact of latent vulnerabilities, run applications with the minimal amount of privileges required for functionality.

Updates are available. Please see the references or vendor advisory for more information.