CVE-2026-7666

LOW

Potential unencrypted email transmission via STARTTLS in the SMTP backend

Title source: cna
STIX 2.1

Description

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.

References (3)

Core 3
Core References
Vendor Advisory vendor-advisory
Django security archive
https://docs.djangoproject.com/en/dev/releases/security/
Mailing List mailing-list
Django releases announcements
https://groups.google.com/g/django-announce
Vendor Advisory vendor-advisory
Django security releases issued: 6.0.6 and 5.2.15
https://www.djangoproject.com/weblog/2026/jun/03/security-releases/

Scores

CVSS v3 3.1
EPSS 0.0016
EPSS Percentile 5.1%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-319
Status published
Products (5)
djangoproject/Django 5.2 - 5.2.15
djangoproject/django 5.2 - 5.2.15
djangoproject/Django 5.2.15
djangoproject/Django 6.0 - 6.0.6
djangoproject/Django 6.0.6
Published Jun 03, 2026
Tracked Since Jun 03, 2026