CVE-2021-21705: Incorrect URL validation in FILTER_VALIDATE_URL
First published: Mon Jun 28 2021(Updated: )
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.
Credit: security@php.net
| Affected Software | Affected Version | How to fix |
|---|---|---|
| PHP PHP | >=7.3.0<7.3.29 | |
| PHP PHP | >=7.4.0<7.4.21 | |
| PHP PHP | >=8.0.0<8.0.8 | |
| NetApp Clustered Data ONTAP | ||
| Oracle SD-WAN Aware | =8.2 | |
| PHP PHP | <8.0.8 | 8.0.8 |
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Reference Links
Frequently Asked Questions
What is the vulnerability ID of this bug?
The vulnerability ID of this bug is CVE-2021-21705.
What is the severity level of CVE-2021-21705?
The severity level of CVE-2021-21705 is medium (5.3).
Which PHP versions are affected by CVE-2021-21705?
PHP versions 7.3.x below 7.3.29, 7.4.x below 7.4.21, and 8.0.x below 8.0.8 are affected by CVE-2021-21705.
How can CVE-2021-21705 be exploited?
CVE-2021-21705 can be exploited by using an URL with an invalid password field that is accepted as valid, leading to incorrect parsing of the URL and potential code execution.
Where can I find more information about CVE-2021-21705?
You can find more information about CVE-2021-21705 at the following references: [reference 1], [reference 2], [reference 3].
- collector/nvd-index
- agent/type
- agent/remedy
- agent/softwarecombine
- agent/references
- agent/author
- agent/weakness
- agent/description
- collector/php-changelog
- source/PHP
- agent/software-canonical-lookup
- collector/mitre-cve
- source/MITRE
- agent/severity
- agent/title
- agent/last-modified-date
- agent/first-publish-date
- agent/tags
- agent/event
- vendor/php
- canonical/php php
- version/php php/7.3.0
- version/php php/7.4.0
- version/php php/8.0.0
- vendor/netapp
- canonical/netapp clustered data ontap
- vendor/oracle
- canonical/oracle sd-wan aware
- version/oracle sd-wan aware/8.2