Critical severity · published Feb 27, 2022
CVE-2021-21708
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…
9.8
CVSS
3%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)3.0% · higher than 87% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PH
PHP · PHP
7.4.0 before 7.4.28; 8.0.0 before 8.0.16; 8.1.0 before 8.1.3 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-21708
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-21708
Exploit
https://bugs.php.net/bug.php?id=81708
Third Party Advisory
https://security.gentoo.org/glsa/202209-20
Third Party Advisory
https://security.netapp.com/advisory/ntap-20220325-0004/
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