CVE-2021-36873

WordPress iQ Block Country <= 1.2.11 - Authenticated Stored Cross-Site Scripting

2021-09-22 23:26

Strategic Overview

Status: Patched in 1.2.12
Affected Plugin: iQ Block Country
Affected Version: <= 1.2.11
CVSS: 5.5Medium
Weakness type: CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE: CVE-2021-36873

View all iQ Block Country vulnerabilities

At a glance

CVE-2021-36873 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the iQ Block Country WordPress plugin, affecting versions <= 1.2.11. It carries a CVSS score of 5.5 (reachable over the network; low attack complexity). Exploitation requires an authenticated account. The issue is fixed in version 1.2.12; sites on affected versions should update now. Disclosed September 2021, reported by R3N0.

Vulnerability Overview

Authenticated Persistent Cross-Site Scripting (XSS) vulnerability in WordPress iQ Block Country plugin (versions <= 1.2.11). Vulnerable parameter: &blockcountry_blockmessage.

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 interaction from a victim user.

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

Reaching this weakness in iQ Block Country <= 1.2.11 takes any authenticated account. 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 iQ Block Country the fix is 1.2.12: builds <= 1.2.11 are affected, anything from 1.2.12 onward is not.

Remediation

Update to version 1.2.12, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to iQ Block Country: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: iQ Block Country 1.2.12 closes this, and updating the plugin is the step that ends it.

Firewall
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2021-36873 https://www.wordfence.com/threat-intel/vulnerabilities/id/b01ce539-08f4-48f7-9ddc-56e87a2c91cc https://nvd.nist.gov/vuln/detail/CVE-2021-36873

Related records

Same weakness class

6.1iQ Block Country < 1.1.20 Reflected Cross-Site Scripting

Other vulnerabilities in iQ Block Country

CVSS Vector

5.5

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:N

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredHigh
User InteractionNone
ScopeChanged
ConfidentialityLow
IntegrityLow
AvailabilityNone

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