CVE-2016-0772
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."
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
Exploits
Public proof-of-concept code below. AS-IS, for defenders and authorised testing only.
Exploit-DB
Python smtplib 2.7.11 / 3.4.4 / 3.5.1 - Man In The Middle StartTLS Stripping
OS impact
SUSE Affected 1 release
| Version | Status | Fixed in |
|---|---|---|
| — | Affected | — |
Debian Fixed 1 release
| Version | Status | Fixed in |
|---|---|---|
| bullseye | Fixed | 2.7.12~rc1-1 |
Application impact
| Vendor | Product | Versions | Fixed |
|---|---|---|---|
| python | python | 3.5.0 | |
| python | python | 3.5.1 | |
| python | python | 3.0 | |
| python | python | 3.0.1 | |
| python | python | 3.1.0 | |
| python | python | 3.1.1 | |
| python | python | 3.1.2 | |
| python | python | 3.1.3 | |
| python | python | 3.1.4 | |
| python | python | 3.1.5 | |
| python | python | 3.2.0 | |
| python | python | 3.2.1 | |
| python | python | 3.2.2 | |
| python | python | 3.2.3 | |
| python | python | 3.2.4 | |
| python | python | 3.2.5 | |
| python | python | 3.2.6 | |
| python | python | 3.3.0 | |
| python | python | 3.3.1 | |
| python | python | 3.3.2 | |
| python | python | 3.3.3 | |
| python | python | 3.3.4 | |
| python | python | 3.3.5 | |
| python | python | 3.3.6 | |
| python | python | 3.4.0 | |
| python | python | 3.4.1 | |
| python | python | 3.4.2 | |
| python | python | 3.4.3 | |
| python | python | 3.4.4 | |
| python | python | {"endIncluding":"2.7.11"} | |
References
- https://www.suse.com/security/cve/CVE-2016-0772.html
- http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00040.html
- http://rhn.redhat.com/errata/RHSA-2016-1626.html
- http://rhn.redhat.com/errata/RHSA-2016-1627.html
- http://rhn.redhat.com/errata/RHSA-2016-1628.html
- http://rhn.redhat.com/errata/RHSA-2016-1629.html
- http://rhn.redhat.com/errata/RHSA-2016-1630.html
- http://www.openwall.com/lists/oss-security/2016/06/14/9
- http://www.securityfocus.com/bid/91225
- http://www.splunk.com/view/SP-CAAAPSV
- http://www.splunk.com/view/SP-CAAAPUE
- https://bugzilla.redhat.com/show_bug.cgi?id=1303647
- https://docs.python.org/3.4/whatsnew/changelog.html#python-3-4-5
- https://docs.python.org/3.5/whatsnew/changelog.html#python-3-5-2
- https://hg.python.org/cpython/raw-file/v2.7.12/Misc/NEWS
- https://hg.python.org/cpython/rev/b3ce713fb9be
- https://hg.python.org/cpython/rev/d590114c2394
- https://lists.debian.org/debian-lts-announce/2019/02/msg00011.html
- https://security.gentoo.org/glsa/201701-18
- https://security-tracker.debian.org/tracker/CVE-2016-0772
CWEs
CWE-693
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.