Vulnerability in Djangoproject Django

CVE-2026-7666

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.

EPSS: 0.002 (4.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 3.1 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-7666?
CVE-2026-7666 is a low-severity vulnerability in Djangoproject Django, classified under Cleartext Transmission of Sensitive Information. CVSS score: 3.1/10. Published 2026-06-03.
How severe is CVE-2026-7666?
Low severity. CVSS v3 base score is 3.1 out of 10.