CVE-2021-24509

Page View Counts <= 2.4.8 - Contributor+ Stored Cross-Site Scripting

2021-07-12 00:00
apple502j

Strategic Overview

Status
Patched in 2.4.9
Affected Plugin
Page View Count
Affected Version
<= 2.4.8
CVSS
5.4Medium
Weakness type
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE
CVE-2021-24509
View all Page View Count vulnerabilities

At a glance

CVE-2021-24509 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the Page View Count WordPress plugin, affecting versions <= 2.4.8. It carries a CVSS score of 5.4 (reachable over the network; low attack complexity). The issue is fixed in version 2.4.9; sites on affected versions should update now. Disclosed July 2021, reported by apple502j.

Vulnerability Overview

The Page View Count WordPress plugin before 2.4.9 does not escape the postid parameter of pvc_stats shortcode, allowing users with a role as low as Contributor to perform Stored XSS attacks. A post made by a contributor would still have to be approved by an admin to have the XSS triggered in the frontend, however, higher privilege users, such as editor could exploit this without the need of approval, and even when the blog disallows the unfiltered_html capability.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed.

CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Reaching this weakness in Page View Count <= 2.4.8 takes a caller who can reach the endpoint. Cross-site scripting happens when input from a request is written into a page without being escaped for the context it lands in, so the browser parses attacker-supplied text as markup or script.

Injected script runs with the privileges of whoever views the affected page, which is how these flaws turn into administrator session theft, silent account creation or persistent backdoors in page content. For Page View Count the fix is 2.4.9: builds <= 2.4.8 are affected, anything from 2.4.9 onward is not.

Remediation

Update to version 2.4.9, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to Page View Count: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Page View Count 2.4.9 closes this, and updating the plugin is the step that ends it.

  • Firewall
  • Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2021-24509https://www.wordfence.com/threat-intel/vulnerabilities/id/f882da12-2db7-481f-9a16-a54e1ab24af5https://nvd.nist.gov/vuln/detail/CVE-2021-24509

Related records

Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C