Strategic Overview
- Status
- Patched in 1.6.4
- Affected Plugin
- WP Shieldon – WordPress Firewall
- Affected Version
<= 1.6.3- CVSS
- 6.1Medium
- Weakness type
- CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
- CVE
CVE-2021-24124
At a glance
CVE-2021-24124 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the WP Shieldon WordPress plugin, affecting versions <= 1.6.3. It carries a CVSS score of 6.1 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 1.6.4; sites on affected versions should update now. Disclosed January 2021, reported by Johto Robbie.
Vulnerability Overview
Unvalidated input and lack of output encoding in the WP Shieldon WordPress plugin, version 1.6.3 and below, leads to Unauthenticated Reflected Cross-Site Scripting (XSS) when the CAPTCHA page is shown could lead to privileged escalation.
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.
CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Reaching this weakness in WP Shieldon <= 1.6.3 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 WP Shieldon the fix is 1.6.4: builds <= 1.6.3 are affected, anything from 1.6.4 onward is not.
Remediation
Update to version 1.6.4, or a newer patched version
How does WordSec protect against this?
The attempt arrives as an ordinary request to WP Shieldon: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: WP Shieldon 1.6.4 closes this, and updating the plugin is the step that ends it.
- Firewall
- Alerts
External References
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