CVE-2016-0772

6.5 MEDIUM
Published: September 02, 2016 Modified: May 06, 2026
View on NVD

Description

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."

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:N

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
http://www.openwall.com/lists/oss-security/2016/06/14/9
Source: secalert@redhat.com
Mailing List
http://www.securityfocus.com/bid/91225
Source: secalert@redhat.com
http://www.splunk.com/view/SP-CAAAPSV
Source: secalert@redhat.com
http://www.splunk.com/view/SP-CAAAPUE
Source: secalert@redhat.com
https://bugzilla.redhat.com/show_bug.cgi?id=1303647
Source: secalert@redhat.com
Issue Tracking Third Party Advisory
https://hg.python.org/cpython/raw-file/v2.7.12/Misc/NEWS
Source: secalert@redhat.com
Release Notes
https://hg.python.org/cpython/rev/b3ce713fb9be
Source: secalert@redhat.com
Patch
https://hg.python.org/cpython/rev/d590114c2394
Source: secalert@redhat.com
Patch
http://rhn.redhat.com/errata/RHSA-2016-1626.html
Source: af854a3a-2127-422b-91ae-364da2661108
http://rhn.redhat.com/errata/RHSA-2016-1627.html
Source: af854a3a-2127-422b-91ae-364da2661108
http://rhn.redhat.com/errata/RHSA-2016-1628.html
Source: af854a3a-2127-422b-91ae-364da2661108
http://rhn.redhat.com/errata/RHSA-2016-1629.html
Source: af854a3a-2127-422b-91ae-364da2661108
http://rhn.redhat.com/errata/RHSA-2016-1630.html
Source: af854a3a-2127-422b-91ae-364da2661108
http://www.openwall.com/lists/oss-security/2016/06/14/9
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List
http://www.securityfocus.com/bid/91225
Source: af854a3a-2127-422b-91ae-364da2661108
http://www.splunk.com/view/SP-CAAAPSV
Source: af854a3a-2127-422b-91ae-364da2661108
http://www.splunk.com/view/SP-CAAAPUE
Source: af854a3a-2127-422b-91ae-364da2661108
https://bugzilla.redhat.com/show_bug.cgi?id=1303647
Source: af854a3a-2127-422b-91ae-364da2661108
Issue Tracking Third Party Advisory
https://docs.python.org/3.4/whatsnew/changelog.html#python-3-4-5
Source: af854a3a-2127-422b-91ae-364da2661108
Release Notes
https://docs.python.org/3.5/whatsnew/changelog.html#python-3-5-2
Source: af854a3a-2127-422b-91ae-364da2661108
Release Notes
https://hg.python.org/cpython/raw-file/v2.7.12/Misc/NEWS
Source: af854a3a-2127-422b-91ae-364da2661108
Release Notes
https://hg.python.org/cpython/rev/b3ce713fb9be
Source: af854a3a-2127-422b-91ae-364da2661108
Patch
https://hg.python.org/cpython/rev/d590114c2394
Source: af854a3a-2127-422b-91ae-364da2661108
Patch
https://security.gentoo.org/glsa/201701-18
Source: af854a3a-2127-422b-91ae-364da2661108

36 reference(s) from NVD

Quick Stats

CVSS v3 Score
6.5 / 10.0
EPSS (Exploit Probability)
7.6%
92th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

Affected Vendors

python