Medium severity · published Oct 4, 2021
CVE-2021-21705
In PHP versions 7.3.x below 7.3.29, 7.4.x below 7.4.21 and 8.0.x below 8.0.8, when using URL validation functionality via filter_var() function with FILTER_VALIDATE_URL parameter,…
5.3
CVSS
2.1%
EPSS
No
On KEV
Description
In PHP versions 7.3.x below 7.3.29, 7.4.x below 7.4.21 and 8.0.x below 8.0.8, when using URL validation functionality via filter_var() function with FILTER_VALIDATE_URL parameter, an URL with invalid password field can be accepted as valid. This can lead to the code incorrectly parsing the URL and potentially leading to other security implications - like contacting a wrong server or making a wrong access decision.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.1% · higher than 82% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PH
PHP · PHP
7.3.0 before 7.3.29; 7.4.0 before 7.4.21; 8.0.0 before 8.0.8 · source: NVD
CD
Clustered Data Ontap · Netapp
All versions, or not specified · source: NVD
SA
Sd-wan Aware · Oracle
8.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-21705
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-21705
Exploit
https://bugs.php.net/bug.php?id=81122
Third Party Advisory
https://security.gentoo.org/glsa/202209-20
Third Party Advisory
https://security.netapp.com/advisory/ntap-20211029-0006/
Patch
https://www.oracle.com/security-alerts/cpujan2022.html
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