Vulnerabilities > CVE-2021-21708 - Use After Free vulnerability in PHP

CVSS 9.8 - CRITICAL

Attack vector

NETWORK

Attack complexity

LOW

Privileges required

NONE

Confidentiality impact

HIGH

Integrity impact

HIGH

Availability impact

HIGH

network

low complexity

php

CWE-416

critical

NVD

Published: 2022-02-27

Updated: 2024-11-21

Summary

In PHP versions 7.4.x below 7.4.28, 8.0.x below 8.0.16, and 8.1.x below 8.1.3, when using filter functions with FILTER_VALIDATE_FLOAT filter and min/max limits, if the filter fails, there is a possibility to trigger use of allocated memory after free, which can result it crashes, and potentially in overwrite of other memory chunks and RCE. This issue affects: code that uses FILTER_VALIDATE_FLOAT with min/max limits.

Vulnerable Configurations

Part	Description	Count
Application	Php PHP PHP 8.1.0 PHP PHP 8.1.1 PHP PHP 8.1.2 PHP PHP 8.0.0 PHP PHP 8.0.1 PHP PHP 8.0.2 PHP PHP 8.0.3 PHP PHP 8.0.4 PHP PHP 8.0.5 PHP PHP 8.0.6 PHP PHP 8.0.7 PHP PHP 8.0.8 PHP PHP 8.0.9 PHP PHP 8.0.10 PHP PHP 8.0.11 PHP PHP 8.0.12 PHP PHP 8.0.13 PHP PHP 8.0.14 PHP PHP 8.0.15 PHP PHP 7.4.0 PHP PHP 7.4.1 PHP PHP 7.4.2 PHP PHP 7.4.3 PHP PHP 7.4.4 PHP PHP 7.4.5 PHP PHP 7.4.6 PHP PHP 7.4.7 PHP PHP 7.4.8 PHP PHP 7.4.9 PHP PHP 7.4.10 PHP PHP 7.4.11 PHP PHP 7.4.12 PHP PHP 7.4.13 PHP PHP 7.4.14 PHP PHP 7.4.15 PHP PHP 7.4.16 PHP PHP 7.4.17 PHP PHP 7.4.18 PHP PHP 7.4.19 PHP PHP 7.4.20 PHP PHP 7.4.21 PHP PHP 7.4.22 PHP PHP 7.4.23 PHP PHP 7.4.24 PHP PHP 7.4.25 PHP PHP 7.4.26 PHP PHP 7.4.27	132

Common Weakness Enumeration (CWE)

CWE-416 - Use After Free

Summary

Vulnerable Configurations

Common Weakness Enumeration (CWE)

References