Constant Contact Forms <= 1.8.7 Editor+ Stored Cross-Site Scripting
Strategic Overview
- Status
- Patched in 1.8.8
- Affected Plugin
- Constant Contact Forms
- Affected Version
< 1.8.8- CVSS
- 5.5Medium
- Weakness type
- CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
- CVE
CVE-2021-24134
At a glance
CVE-2021-24134 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the Constant Contact Forms WordPress plugin, affecting versions < 1.8.8. It carries a CVSS score of 5.5 (reachable over the network; low attack complexity). The issue is fixed in version 1.8.8; sites on affected versions should update now. Disclosed September 2020, reported by Nguyen Anh Tien.
Vulnerability Overview
Unvalidated input and lack of output encoding in the Constant Contact Forms WordPress plugin, versions before 1.8.8, lead to multiple Stored Cross-Site Scripting vulnerabilities, which allowed high-privileged user (Editor+) to inject arbitrary JavaScript code or HTML in posts where the malicious form is embed.
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 Constant Contact Forms < 1.8.8 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 Constant Contact Forms the fix is 1.8.8: builds < 1.8.8 are affected, anything from 1.8.8 onward is not.
Remediation
Update to version 1.8.8, or a newer patched version
How does WordSec protect against this?
The attempt arrives as an ordinary request to Constant Contact Forms: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Constant Contact Forms 1.8.8 closes this, and updating the plugin is the step that ends it.
- Firewall
- Alerts
External References
Related records
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