CVE-2021-24134
Constant Contact Forms < 1.8.8 - Multiple Authenticated Stored XSS
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- High
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
4.8
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.
- Record
CVE-2021-24134- CVSS 3.1
- 4.8 Medium
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N - CVSS 2.0
- 3.5 Low
AV:N/AC:M/Au:S/C:N/I:P/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
CVE List No score
Constant Contact Forms < 1.8.8 - Multiple Authenticated Stored XSS
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.
- Record
CVE-2021-24134- Weakness
- CWE-79
- Updated
- 2026-11-02
EUVDEUVD-2021-11048 No score
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.
- Record
EUVD-2021-11048- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-5gq5-98jg-gqqf No score
Unvalidated input and lack of output encoding in the Constant Contact Forms WordPress plugin,...
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.
- Record
GHSA-5gq5-98jg-gqqf- Weakness
- CWE-79
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, products | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-24134 is a medium vulnerability (CVSS 4.8) in Constant Contact Forms, published March 18, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.65%, the 51st percentile. No source names a fixed version.