CVE-2016-0772

high-risk
Published 2016-09-02

The smtplib library in CPython (aka Python) before 2.7.12, 3.x before 3.4.5, and 3.5.x before 3.5.2 does not return an error when StartTLS fails, which might allow man-in-the-middle attackers to bypass the TLS protections by leveraging a network position between the client and the registry to block the StartTLS command, aka a "StartTLS stripping attack."

Do I need to act?

~
5.8% chance of exploitation in next 30 days
EPSS score — moderate exploit probability
-
Not on CISA KEV list
No confirmed active exploitation reported to CISA
!
1 public exploit available
?
Patch status unknown
Check vendor advisories for fix availability and mitigation guidance
6
CVSS 6.5/10 Medium
NETWORK / HIGH complexity

Affected Vendors

51
/ 100
high-risk
Severity 20/34 · Moderate
Exploitability 9/34 · Low
Exposure 22/34 · High