CVE-2021-25086

Advanced Page Visit Counter <= 5.0.8 - Unauthenticated Cross-Site Scripting

2022-04-05 00:00
Krzysztof Zając

Strategic Overview

Status
Patched in 6.0.0
Affected Plugin
Advanced Page Visit Counter – Most Wanted Analytics Plugin for WordPress
Affected Version
<= 5.0.8
CVSS
7.2High
Weakness type
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE
CVE-2021-25086
View all Advanced Page Visit Counter – Most Wanted Analytics Plugin for WordPress vulnerabilities

At a glance

CVE-2021-25086 is a high-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the Advanced Page Visit Counter WordPress plugin, affecting versions <= 5.0.8. It carries a CVSS score of 7.2 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 6.0.0; sites on affected versions should update now. Disclosed April 2022, reported by Krzysztof Zając.

Vulnerability Overview

The Advanced Page Visit Counter WordPress plugin through 5.0.8 does not sanitise and escape some input before outputting it in an admin dashboard page, allowing unauthenticated attackers to perform Cross-Site Scripting attacks against admins viewing it

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user.

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

Reaching this weakness in Advanced Page Visit Counter <= 5.0.8 takes no account at all. 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 Advanced Page Visit Counter the fix is 6.0.0: builds <= 5.0.8 are affected, anything from 6.0.0 onward is not.

Remediation

Update to version 6.0.0, or a newer patched version

How does WordSec protect against this?

Requests carrying this pattern arrive without a session, so nothing upstream of the firewall gets a chance to reject them: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Advanced Page Visit Counter 6.0.0 closes this, and updating the plugin is the step that ends it.

  • Firewall
  • Login Security
  • Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2021-25086https://www.wordfence.com/threat-intel/vulnerabilities/id/f444568c-fe4c-4fa6-9b83-2d069f851360https://nvd.nist.gov/vuln/detail/CVE-2021-25086

Related records

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