# CVE-2026-114716: Roundcube Webmail mail header injection in inline image data URI

Source: https://junglewise.ai/threats/cve-2026-114716-roundcube-webmail-before-1-6-20-and-1-7-x-before-1-7-5-is  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-22. Updated: 2026-10-22  
License: CC BY 4.0 with a link back

CVE-2026-114716 · Severity: high · CVSS 8.5 · Published 2026-10-22

Roundcube Webmail is an email client that allows users to send and receive messages. A vulnerability in how it processes inline images allows authenticated attackers to inject arbitrary email headers into outgoing messages, potentially enabling mail spoofing or other mail-based attacks.

Technologies: [Roundcube Webmail](https://junglewise.ai/threats/technologies/webmail). Vendors: [Roundcube](https://junglewise.ai/threats/vendors/roundcube).

## Quick answers

**Is CVE-2026-114716 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-114716 being exploited in the wild.

**How severe is CVE-2026-114716?** High severity, with a CVSS score of 8.5, published 22 October 2026.

**Which products and versions are affected?** Roundcube Webmail before 1.6.20; 1.7.0 to 1.7.4.

**Is there a fix for CVE-2026-114716?** Yes: fixed in Roundcube Webmail 1.6.20, 1.7.5. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-114716 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-114716?** Check whether you run Roundcube Webmail at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- Fixed in Roundcube Webmail 1.6.20, 1.7.5

## Technical details

The rcmail_sendmail::extract_inline_images() function fails to validate the media type extracted from inline image data URIs, allowing CRLF injection into MIME headers. An authenticated attacker can inject arbitrary headers by crafting a data URI with newlines in the media type field. The fix validates media types using rcube_mime::is_mimetype_valid().

## Affected products

- Roundcube Webmail before 1.6.20; 1.7.0 to 1.7.4

## Timeline

- 2026-10-22: disclosed
- 2026-10-19: patched

## References

- [https://bugs.debian.org/1151279](https://bugs.debian.org/1151279)
- [https://github.com/roundcube/roundcubemail/commit/7f3cc9cacb16cb3ab047fe8e3cba81db2023cdfc](https://github.com/roundcube/roundcubemail/commit/7f3cc9cacb16cb3ab047fe8e3cba81db2023cdfc)

## Related threats

- [Roundcube Webmail improper authentication in multi-host installations](https://junglewise.ai/threats/cve-2026-114732-roundcube-webmail-before-1-6-20-and-1-7-x-before-1-7-5-is)
- [Roundcube Webmail uncontrolled resource consumption in CSS proxy](https://junglewise.ai/threats/cve-2026-114731-roundcube-webmail-before-1-6-20-and-1-7-x-before-1-7-5-is)
- [Roundcube Webmail server-side request forgery filter bypass](https://junglewise.ai/threats/cve-2026-114730-roundcube-webmail-1-6-14-before-1-6-20-and-1-7-0-before-1-7-5-is)
- [Roundcube Webmail content blocking bypass via SVG SMIL](https://junglewise.ai/threats/cve-2026-114729-roundcube-webmail-before-1-6-20-and-1-7-x-before-1-7-5-is)
- [Roundcube Webmail remote content blocking bypass in CSS FuncIRI handling](https://junglewise.ai/threats/cve-2026-114728-roundcube-webmail-before-1-6-20-and-1-7-x-before-1-7-5-is)