CVE-2026-7666
Potential unencrypted email transmission via STARTTLS in the SMTP backend
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.
How to fix CVE-2026-7666
To remediate CVE-2026-7666, upgrade the affected package to a fixed version below.
- Bitnami/django—upgrade to 5.2.15 or later
- —no fix listed
- —upgrade to 5.2.15 or later
Is CVE-2026-7666 being exploited?
No exploitation signal available. Neither CISA KEV nor a current EPSS score has been published for CVE-2026-7666.
Affected packages (3)
- >= 5.2.0, < 5.2.15, >= 6.0.0, < 6.0.6
- from 0
- >= 5.2, < 5.2.15, >= 6.0, < 6.0.6
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |