CVE-2021-21708 HIGH

CVE-2021-21708: UAF due to php_filter_float() failing

Vendor Php Group
Product PHP
Weakness CWE-416
Published February 27, 2022
Last update September 17, 2024
View on NVD All CVEs

CVSS base score

8.2/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality None
Integrity High

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

February 27, 2022 CVE published
September 17, 2024 Record updated