CVE-2026-7666

Potential unencrypted email transmission via STARTTLS in the SMTP backend

LOW
3.1
CVSS Score
Published: June 3, 2026 at 01:16 PM UTC
Updated: July 21, 2026 at 07:26 PM UTC
1 product affected across 1 vendorDjango

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Severity
LOW3.1
Exploit prediction
EPSS 0.1%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

5.2 ≤ v < 5.2.156.0 ≤ v < 6.0.65.26.0
Vendor states this is fixed in 5.2.15 (unaffected)
Vendor states this is fixed in 6.0.6 (unaffected)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (3)

Mailing ListRelease Notes
Source: cverecord
https://groups.google.com/g/django-announce

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

3.1LOWDSF
Vector?

Quick Info

StatusANALYZED
CWE
CWE-319

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