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TI-2016-00691 Aliases CVE-2016-0772GHSA-6m57-q338-h677

The smtplib library in CPython (aka Python) before 2.7.12, 3.x before 3.4.5, and 3.5.x…

Priority MEDIUM 45CWE-693Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
Impact type
Security bypass
Confidentiality · integrity · availability
Low · High · None
Fix status
Partial Red Hat: 24 fixed, 1 without a fix

Attack profile from CVSS 3.0 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-693.

Summary

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."

Why it matters now

EPSS 0.15352 96th percentileScored 2026-11-07
Fix Partial Red Hat: 5 advisoriesRed Hat: 24 fixed, 1 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 30

CPEVersionsRoleVendor
cpe:2.3:a:python:python:3.5.0:*:*:*:*:*:*:*3.5.0Vulnerablepython-pillow
cpe:2.3:a:python:python:3.5.1:*:*:*:*:*:*:*3.5.1Vulnerablepython-pillow
cpe:2.3:a:python:python:3.0:*:*:*:*:*:*:*3.0Vulnerablepython-pillow
cpe:2.3:a:python:python:3.0.1:*:*:*:*:*:*:*3.0.1Vulnerablepython-pillow
cpe:2.3:a:python:python:3.1.0:*:*:*:*:*:*:*3.1.0Vulnerablepython-pillow
cpe:2.3:a:python:python:3.1.1:*:*:*:*:*:*:*3.1.1Vulnerablepython-pillow
cpe:2.3:a:python:python:3.1.2:*:*:*:*:*:*:*3.1.2Vulnerablepython-pillow
cpe:2.3:a:python:python:3.1.3:*:*:*:*:*:*:*3.1.3Vulnerablepython-pillow
cpe:2.3:a:python:python:3.1.4:*:*:*:*:*:*:*3.1.4Vulnerablepython-pillow
cpe:2.3:a:python:python:3.1.5:*:*:*:*:*:*:*3.1.5Vulnerablepython-pillow
  • cpe:2.3:a:python:python:3.5.0:*:*:*:*:*:*:* Versions 3.5.0 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.5.1:*:*:*:*:*:*:* Versions 3.5.1 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.0:*:*:*:*:*:*:* Versions 3.0 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.0.1:*:*:*:*:*:*:* Versions 3.0.1 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.1.0:*:*:*:*:*:*:* Versions 3.1.0 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.1.1:*:*:*:*:*:*:* Versions 3.1.1 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.1.2:*:*:*:*:*:*:* Versions 3.1.2 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.1.3:*:*:*:*:*:*:* Versions 3.1.3 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.1.4:*:*:*:*:*:*:* Versions 3.1.4 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.1.5:*:*:*:*:*:*:* Versions 3.1.5 Vulnerable ·python-pillow
Show 20 more CPE
CPEVersionsRoleVendor
cpe:2.3:a:python:python:3.2.0:*:*:*:*:*:*:*3.2.0Vulnerablepython-pillow
cpe:2.3:a:python:python:3.2.1:*:*:*:*:*:*:*3.2.1Vulnerablepython-pillow
cpe:2.3:a:python:python:3.2.2:*:*:*:*:*:*:*3.2.2Vulnerablepython-pillow
cpe:2.3:a:python:python:3.2.3:*:*:*:*:*:*:*3.2.3Vulnerablepython-pillow
cpe:2.3:a:python:python:3.2.4:*:*:*:*:*:*:*3.2.4Vulnerablepython-pillow
cpe:2.3:a:python:python:3.2.5:*:*:*:*:*:*:*3.2.5Vulnerablepython-pillow
cpe:2.3:a:python:python:3.2.6:*:*:*:*:*:*:*3.2.6Vulnerablepython-pillow
cpe:2.3:a:python:python:3.3.0:*:*:*:*:*:*:*3.3.0Vulnerablepython-pillow
cpe:2.3:a:python:python:3.3.1:*:*:*:*:*:*:*3.3.1Vulnerablepython-pillow
cpe:2.3:a:python:python:3.3.2:*:*:*:*:*:*:*3.3.2Vulnerablepython-pillow
cpe:2.3:a:python:python:3.3.3:*:*:*:*:*:*:*3.3.3Vulnerablepython-pillow
cpe:2.3:a:python:python:3.3.4:*:*:*:*:*:*:*3.3.4Vulnerablepython-pillow
cpe:2.3:a:python:python:3.3.5:*:*:*:*:*:*:*3.3.5Vulnerablepython-pillow
cpe:2.3:a:python:python:3.3.6:*:*:*:*:*:*:*3.3.6Vulnerablepython-pillow
cpe:2.3:a:python:python:3.4.0:*:*:*:*:*:*:*3.4.0Vulnerablepython-pillow
cpe:2.3:a:python:python:3.4.1:*:*:*:*:*:*:*3.4.1Vulnerablepython-pillow
cpe:2.3:a:python:python:3.4.2:*:*:*:*:*:*:*3.4.2Vulnerablepython-pillow
cpe:2.3:a:python:python:3.4.3:*:*:*:*:*:*:*3.4.3Vulnerablepython-pillow
cpe:2.3:a:python:python:3.4.4:*:*:*:*:*:*:*3.4.4Vulnerablepython-pillow
cpe:2.3:a:python:python:*:*:*:*:*:*:*:*up to 2.7.11Vulnerablepython-pillow
  • cpe:2.3:a:python:python:3.2.0:*:*:*:*:*:*:* Versions 3.2.0 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.2.1:*:*:*:*:*:*:* Versions 3.2.1 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.2.2:*:*:*:*:*:*:* Versions 3.2.2 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.2.3:*:*:*:*:*:*:* Versions 3.2.3 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.2.4:*:*:*:*:*:*:* Versions 3.2.4 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.2.5:*:*:*:*:*:*:* Versions 3.2.5 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.2.6:*:*:*:*:*:*:* Versions 3.2.6 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.3.0:*:*:*:*:*:*:* Versions 3.3.0 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.3.1:*:*:*:*:*:*:* Versions 3.3.1 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.3.2:*:*:*:*:*:*:* Versions 3.3.2 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.3.3:*:*:*:*:*:*:* Versions 3.3.3 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.3.4:*:*:*:*:*:*:* Versions 3.3.4 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.3.5:*:*:*:*:*:*:* Versions 3.3.5 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.3.6:*:*:*:*:*:*:* Versions 3.3.6 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.4.0:*:*:*:*:*:*:* Versions 3.4.0 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.4.1:*:*:*:*:*:*:* Versions 3.4.1 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.4.2:*:*:*:*:*:*:* Versions 3.4.2 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.4.3:*:*:*:*:*:*:* Versions 3.4.3 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.4.4:*:*:*:*:*:*:* Versions 3.4.4 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:*:*:*:*:*:*:*:* Versions up to 2.7.11 Vulnerable ·python-pillow

Remediation

Red Hat 5 advisories

  • RHSA-2016:1629 Released 2016-08-18 · Red Hat rating Moderate
    python33-python security update
    • Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 6) python33-python-3.3.2-18.el6, python33-python-debug-3.3.2-18.el6, python33-python-devel-3.3.2-18.el6 +4
    • Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 7) python33-python-3.3.2-16.el7, python33-python-debug-3.3.2-16.el7, python33-python-devel-3.3.2-16.el7 +4
    • Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 6.6) python33-python-3.3.2-18.el6, python33-python-debug-3.3.2-18.el6, python33-python-devel-3.3.2-18.el6 +4
    • Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 6.7) python33-python-3.3.2-18.el6, python33-python-debug-3.3.2-18.el6, python33-python-devel-3.3.2-18.el6 +4
    • Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.1) python33-python-3.3.2-16.el7, python33-python-debug-3.3.2-16.el7, python33-python-devel-3.3.2-16.el7 +4
    • Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.2) python33-python-3.3.2-16.el7, python33-python-debug-3.3.2-16.el7, python33-python-devel-3.3.2-16.el7 +4
    • Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 6) python33-python-3.3.2-18.el6, python33-python-debug-3.3.2-18.el6, python33-python-devel-3.3.2-18.el6 +4
    • Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 7) python33-python-3.3.2-16.el7, python33-python-debug-3.3.2-16.el7, python33-python-devel-3.3.2-16.el7 +4
  • RHSA-2016:1630 Released 2016-08-18 · Red Hat rating Moderate
    rh-python34-python security update
    • Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 6) rh-python34-python-3.4.2-14.el6, rh-python34-python-debug-3.4.2-14.el6, rh-python34-python-devel-3.4.2-14.el6 +4
    • Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 7) rh-python34-python-3.4.2-13.el7, rh-python34-python-debug-3.4.2-13.el7, rh-python34-python-devel-3.4.2-13.el7 +4
    • Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 6.6) rh-python34-python-3.4.2-14.el6, rh-python34-python-debug-3.4.2-14.el6, rh-python34-python-devel-3.4.2-14.el6 +4
    • Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 6.7) rh-python34-python-3.4.2-14.el6, rh-python34-python-debug-3.4.2-14.el6, rh-python34-python-devel-3.4.2-14.el6 +4
    • Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.1) rh-python34-python-3.4.2-13.el7, rh-python34-python-debug-3.4.2-13.el7, rh-python34-python-devel-3.4.2-13.el7 +4
    • Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.2) rh-python34-python-3.4.2-13.el7, rh-python34-python-debug-3.4.2-13.el7, rh-python34-python-devel-3.4.2-13.el7 +4
    • Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 6) rh-python34-python-3.4.2-14.el6, rh-python34-python-debug-3.4.2-14.el6, rh-python34-python-devel-3.4.2-14.el6 +4
    • Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 7) rh-python34-python-3.4.2-13.el7, rh-python34-python-debug-3.4.2-13.el7, rh-python34-python-devel-3.4.2-13.el7 +4
  • RHSA-2016:1628 Released 2016-08-18 · Red Hat rating Moderate
    python27-python security update
    • Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 6) python27-python-2.7.8-18.el6, python27-python-debug-2.7.8-18.el6, python27-python-devel-2.7.8-18.el6 +4
    • Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 7) python27-python-2.7.8-16.el7, python27-python-debug-2.7.8-16.el7, python27-python-devel-2.7.8-16.el7 +4
    • Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 6.6) python27-python-2.7.8-18.el6, python27-python-debug-2.7.8-18.el6, python27-python-devel-2.7.8-18.el6 +4
    • Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 6.7) python27-python-2.7.8-18.el6, python27-python-debug-2.7.8-18.el6, python27-python-devel-2.7.8-18.el6 +4
    • Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.1) python27-python-2.7.8-16.el7, python27-python-debug-2.7.8-16.el7, python27-python-devel-2.7.8-16.el7 +4
    • Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.2) python27-python-2.7.8-16.el7, python27-python-debug-2.7.8-16.el7, python27-python-devel-2.7.8-16.el7 +4
    • Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 6) python27-python-2.7.8-18.el6, python27-python-debug-2.7.8-18.el6, python27-python-devel-2.7.8-18.el6 +4
    • Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 7) python27-python-2.7.8-16.el7, python27-python-debug-2.7.8-16.el7, python27-python-devel-2.7.8-16.el7 +4
Show 2 more Red Hat advisories
  • RHSA-2016:1626 Released 2016-08-18 · Red Hat rating Moderate
    python security update
    • Red Hat Enterprise Linux Client (v. 7) python-2.7.5-38.el7_2, python-libs-2.7.5-38.el7_2
    • Red Hat Enterprise Linux Client Optional (v. 7) python-debug-2.7.5-38.el7_2, python-devel-2.7.5-38.el7_2, python-test-2.7.5-38.el7_2 +2
    • Red Hat Enterprise Linux ComputeNode (v. 7) python-2.7.5-38.el7_2, python-devel-2.7.5-38.el7_2, python-libs-2.7.5-38.el7_2
    • Red Hat Enterprise Linux ComputeNode Optional (v. 7) python-debug-2.7.5-38.el7_2, python-test-2.7.5-38.el7_2, python-tools-2.7.5-38.el7_2 +1
    • Red Hat Enterprise Linux Desktop (v. 6) python-2.6.6-66.el6_8, python-libs-2.6.6-66.el6_8, tkinter-2.6.6-66.el6_8
    • Red Hat Enterprise Linux Desktop Optional (v. 6) python-devel-2.6.6-66.el6_8, python-test-2.6.6-66.el6_8, python-tools-2.6.6-66.el6_8
    • Red Hat Enterprise Linux HPC Node (v. 6) python-2.6.6-66.el6_8, python-devel-2.6.6-66.el6_8, python-libs-2.6.6-66.el6_8
    • Red Hat Enterprise Linux HPC Node Optional (v. 6) python-test-2.6.6-66.el6_8, python-tools-2.6.6-66.el6_8, tkinter-2.6.6-66.el6_8
    • Red Hat Enterprise Linux Server (v. 6) python-2.6.6-66.el6_8, python-devel-2.6.6-66.el6_8, python-devel-2.6.6-66.el6_8.ppc +3
    • Red Hat Enterprise Linux Server (v. 7) python-2.7.5-38.el7_2, python-devel-2.7.5-38.el7_2, python-libs-2.7.5-38.el7_2 +1
    • Red Hat Enterprise Linux Server Optional (v. 6) python-test-2.6.6-66.el6_8, python-tools-2.6.6-66.el6_8, tkinter-2.6.6-66.el6_8
    • Red Hat Enterprise Linux Server Optional (v. 7) python-debug-2.7.5-38.el7_2, python-test-2.7.5-38.el7_2, python-tools-2.7.5-38.el7_2 +1
    • Red Hat Enterprise Linux Workstation (v. 6) python-2.6.6-66.el6_8, python-devel-2.6.6-66.el6_8, python-libs-2.6.6-66.el6_8 +1
    • Red Hat Enterprise Linux Workstation (v. 7) python-2.7.5-38.el7_2, python-devel-2.7.5-38.el7_2, python-libs-2.7.5-38.el7_2
    • Red Hat Enterprise Linux Workstation Optional (v. 6) python-test-2.6.6-66.el6_8, python-tools-2.6.6-66.el6_8
    • Red Hat Enterprise Linux Workstation Optional (v. 7) python-debug-2.7.5-38.el7_2, python-test-2.7.5-38.el7_2, python-tools-2.7.5-38.el7_2 +1
  • RHSA-2016:1627 Released 2016-08-18 · Red Hat rating Moderate
    rh-python35-python security update
    • Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 7) rh-python35-python-3.5.1-9.el7, rh-python35-python-debug-3.5.1-9.el7, rh-python35-python-devel-3.5.1-9.el7 +4
    • Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.1) rh-python35-python-3.5.1-9.el7, rh-python35-python-debug-3.5.1-9.el7, rh-python35-python-devel-3.5.1-9.el7 +4
    • Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.2) rh-python35-python-3.5.1-9.el7, rh-python35-python-debug-3.5.1-9.el7, rh-python35-python-devel-3.5.1-9.el7 +4
    • Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 7) rh-python35-python-3.5.1-9.el7, rh-python35-python-debug-3.5.1-9.el7, rh-python35-python-devel-3.5.1-9.el7 +4

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 5AffectedNo fix planned: Will not fix
Red Hat Enterprise Linux Client (v. 7)Fixed RHSA-2016:1626
Red Hat Enterprise Linux Client Optional (v. 7)Fixed RHSA-2016:1626
Red Hat Enterprise Linux ComputeNode (v. 7)Fixed RHSA-2016:1626
Red Hat Enterprise Linux ComputeNode Optional (v. 7)Fixed RHSA-2016:1626
Red Hat Enterprise Linux Desktop (v. 6)Fixed RHSA-2016:1626
Red Hat Enterprise Linux Desktop Optional (v. 6)Fixed RHSA-2016:1626
Red Hat Enterprise Linux HPC Node (v. 6)Fixed RHSA-2016:1626
Red Hat Enterprise Linux HPC Node Optional (v. 6)Fixed RHSA-2016:1626
Red Hat Enterprise Linux Server (v. 6)Fixed RHSA-2016:1626
Red Hat Enterprise Linux Server (v. 7)Fixed RHSA-2016:1626
Red Hat Enterprise Linux Server Optional (v. 6)Fixed RHSA-2016:1626
Red Hat Enterprise Linux Server Optional (v. 7)Fixed RHSA-2016:1626
Red Hat Enterprise Linux Workstation (v. 6)Fixed RHSA-2016:1626
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2016:1626
Red Hat Enterprise Linux Workstation Optional (v. 6)Fixed RHSA-2016:1626
Red Hat Enterprise Linux Workstation Optional (v. 7)Fixed RHSA-2016:1626
Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 6)Fixed RHSA-2016:1628, RHSA-2016:1629, RHSA-2016:1630
Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 7)Fixed RHSA-2016:1627, RHSA-2016:1628, RHSA-2016:1629, RHSA-2016:1630
Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 6.6)Fixed RHSA-2016:1628, RHSA-2016:1629, RHSA-2016:1630
Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 6.7)Fixed RHSA-2016:1628, RHSA-2016:1629, RHSA-2016:1630
Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.1)Fixed RHSA-2016:1627, RHSA-2016:1628, RHSA-2016:1629, RHSA-2016:1630
Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.2)Fixed RHSA-2016:1627, RHSA-2016:1628, RHSA-2016:1629, RHSA-2016:1630
Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 6)Fixed RHSA-2016:1628, RHSA-2016:1629, RHSA-2016:1630
Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2016:1627, RHSA-2016:1628, RHSA-2016:1629, RHSA-2016:1630

Timeline

  1. 2026-10-02 Threatist record created from CVE-2016-0772
  2. 2026-10-03 Alias added: GHSA-6m57-q338-h677

References

Patch 2

Advisory 8

Other 7

  • TI-2016-01993 The DES and Triple DES ciphers, as used in the TLS, SSH, and IPSec protocols and other… CVSS 3.1HIGH 7.5
  • TI-2022-24108 An XML External Entity (XXE) issue was discovered in Python through 3.9.1. CVSS 3.1CRITICAL 9.8
  • TI-2022-17508 The Keccak XKCP SHA-3 reference implementation before fdc6fef has an integer overflow and… CVSS 3.1CRITICAL 9.8
  • TI-2021-02254 Python 3.x through 3.9.1 has a buffer overflow in PyCArg_repr in _ctypes/callproc.c… CVSS 3.1CRITICAL 9.8
  • TI-2007-04413 Directory traversal vulnerability in the (1) extract and (2) extractall functions in the… CVSS 3.1CRITICAL 9.8
  • TI-2014-00217 OpenSSL before 0.9.8za, 1.0.0 before 1.0.0m, and 1.0.1 before 1.0.1h does not properly… CVSS 3.1HIGH 7.4
See all 139 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences