CVE-2021-34667

Public Exploit
Calendar_plugin <= 1.0 Reflected Cross-Site Scripting

Description

The Calendar_plugin WordPress plugin is vulnerable to Reflected Cross-Site Scripting due to the use of `$_SERVER['PHP_SELF']` in the ~/calendar.php file which allows attackers to inject arbitrary web scripts, in versions up to and including 1.0.

Remediation

Solution:

  • Uninstall the plugin

Category

6.1
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.21%
Third-Party Advisory wordpress.org Third-Party Advisory wordfence.com
Affected: Calendar_plugin Calendar_plugin
Published at:
Updated at:

References

Link Tags
https://www.wordfence.com/vulnerability-advisories/#CVE-2021-34667 third party advisory exploit
https://plugins.trac.wordpress.org/browser/calendar-plugin/trunk/calendar.php#L86 third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2021-34667?
CVE-2021-34667 has been scored as a medium severity vulnerability.
How to fix CVE-2021-34667?
To fix CVE-2021-34667: Uninstall the plugin
Is CVE-2021-34667 being actively exploited in the wild?
It is possible that CVE-2021-34667 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-34667?
CVE-2021-34667 affects Calendar_plugin Calendar_plugin.
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