CVE-2026-7666

LOW 3.1

Potential unencrypted email transmission via STARTTLS in the SMTP backend

CVSS Score

3.1

EPSS Score

0.0%

EPSS Percentile

0th

An issue was discovered in Django 6.0 before 6.0.6 and 5.2 before 5.2.15. `django.core.mail.backends.smtp.EmailBackend` in Django fails to prevent reuse of a partially-initialized connection after a failed `STARTTLS` handshake when `fail_silently=True`, which allows on-path network attackers to read email content via cleartext interception. Earlier, unsupported Django series (such as 5.0.x, 4.1.x, and 3.2.x) were not evaluated and may also be affected. Django would like to thank Kasper Dupont for reporting this issue.

CWE	CWE-319
Vendor	djangoproject
Product	django
Published	Jun 3, 2026
Last Updated	Jun 3, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N

Attack Vector

Attack Complexity

Privileges Required

User Interaction

Scope

Confidentiality

Integrity

Availability

Affected Versions

djangoproject / Django

6.0 < 6.0.6 5.2 < 5.2.15

References

NVD ↗ CVE.org ↗ EPSS Data ↗

docs.djangoproject.com: https://docs.djangoproject.com/en/dev/releases/security/ groups.google.com: https://groups.google.com/g/django-announce djangoproject.com: https://www.djangoproject.com/weblog/2026/jun/03/security-releases/

Credits

🔍 Kasper Dupont Jake Howard Natalia Bidart