# CVE-2026-7666: Django cleartext email transmission in SMTP EmailBackend

Source: https://junglewise.ai/threats/cve-2026-7666-django-cleartext-email-transmission-in-smtp-emailbackend  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-03. Updated: 2026-07-13  
License: CC BY 4.0 with a link back

CVE-2026-7666 · Severity: medium · CVSS 4 · Published 2026-06-03

Django, a popular web framework, contains a flaw in how it handles secure email connections. When configured to ignore errors, the system may continue to send emails over an unencrypted connection if the initial security handshake fails. This could allow an attacker positioned on the network to intercept and read sensitive email content.

Technologies: [Django (PyPI)](https://junglewise.ai/threats/technologies/django). Vendors: [PyPI](https://junglewise.ai/threats/vendors/pypi).

## Quick answers

**Is CVE-2026-7666 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-7666 being exploited in the wild.

**How severe is CVE-2026-7666?** Medium severity, with a CVSS score of 4, published 3 June 2026.

**Which products and versions are affected?** Django (PyPI) ECOSYSTEM:introduced=5.2,fixed=5.2.15, ECOSYSTEM:introduced=5.2,fixed=5.2.15,introduced=6.0,fixed=6.0.6.

**Is there a fix for CVE-2026-7666?** Yes. Django (PyPI): upgrade to 5.2.15, 6.0.6 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-7666 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-7666?** Check whether you run Django (PyPI) 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

- Django (PyPI): upgrade to 5.2.15, 6.0.6 or later

  ```sh
  pip install "Django>=6.0.6"
  ```


## Technical details

The vulnerability exists in django.core.mail.backends.smtp.EmailBackend. When the 'fail_silently' parameter is set to True, the backend does not properly terminate the connection if the STARTTLS handshake fails. Instead, it may proceed to transmit email data over the existing unencrypted socket. An on-path attacker (Man-in-the-Middle) can trigger a handshake failure to force the transmission of sensitive data in cleartext. The issue is fixed in Django versions 5.2.15 and 6.0.6. Older, unsupported versions like 3.2, 4.1, and 5.0 may also be affected but were not explicitly tested.

## Affected products

- Django Software Foundation Django >= 5.2, < 5.2.15; >= 6.0, < 6.0.6

## Identifiers

- CVE-2026-7666
- GHSA-mm6v-q8q9-pgcf
- PYSEC-2026-200

## Timeline

- 2026-06-03: disclosed
- 2026-06-03: advisory
- 2026-06-03: patched

## References

- [https://docs.djangoproject.com/en/dev/releases/security](https://docs.djangoproject.com/en/dev/releases/security)
- [https://groups.google.com/g/django-announce](https://groups.google.com/g/django-announce)
- [https://www.djangoproject.com/weblog/2026/jun/03/security-releases](https://www.djangoproject.com/weblog/2026/jun/03/security-releases)
- [https://github.com/pypa/advisory-database/tree/main/vulns/django/PYSEC-2026-200.yaml](https://github.com/pypa/advisory-database/tree/main/vulns/django/PYSEC-2026-200.yaml)

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