CVE-2026-7666 (GCVE-0-2026-7666)
Vulnerability from cvelistv5 – Published: 2026-06-03 13:16 – Updated: 2026-06-03 15:43
VLAI
Title
Potential unencrypted email transmission via STARTTLS in the SMTP backend
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
- CWE-319 - Cleartext Transmission of Sensitive Information
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://docs.djangoproject.com/en/dev/releases/se… | vendor-advisory |
| https://groups.google.com/g/django-announce | mailing-list |
| https://www.djangoproject.com/weblog/2026/jun/03/… | vendor-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| djangoproject | Django |
Affected:
6.0 , < 6.0.6
(python)
Unaffected: 6.0.6 (python) Affected: 5.2 , < 5.2.15 (python) Unaffected: 5.2.15 (python) |
Date Public
2026-06-03 08:00
Credits
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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