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Fencer Vulns
high 7.2

CVE-2020-26116 json

http.client in Python 3.x before 3.5.10, 3.6.x before 3.6.12, 3.7.x before 3.7.9, and 3.8.x before 3.8.5 allows CRLF injection if the attac…

published 2020-09-27 6 y ago modified 2026-10-14 26 d ago also BIT-libpython-2020-26116 , BIT-python-2020-26116 , BIT-python-min-2020-26116 , EUVD-2020-18746

cvss
7.2
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
6.4%
EPSS 6.4% chance of exploitation in 30 days, percentile 93%
public exploits
0
none known

Summary

http.client in Python 3.x before 3.5.10, 3.6.x before 3.6.12, 3.7.x before 3.7.9, and 3.8.x before 3.8.5 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of HTTPConnection.request.

Patch / fix

  • bitnami libpython 3.5.10, 3.6.12, 3.7.9, 3.8.5
  • bitnami python 3.5.10, 3.6.12, 3.7.9, 3.8.5
  • bitnami python-min 3.5.10, 3.6.12, 3.7.9, 3.8.5
  • Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP V3.1.5
  • Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP V3.1.5
  • Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP V3.1.5
  • pypy3 Debian 14, Debian 13, Debian 12 7.3.3+dfsg-1

debian advisories DEBIAN-CVE-2020-26116

  • python3.5 Ubuntu 16.04 LTS 3.5.2-2ubuntu0~16.04.12
  • python3.6 Ubuntu 18.04 LTS 3.6.9-1~18.04ubuntu1.3
  • python3.4 Ubuntu Pro 14.04 LTS 3.4.3-1ubuntu1~14.04.7+esm8
  • python3.5 Ubuntu Pro 14.04 LTS 3.5.2-2ubuntu0~16.04.4~14.04.1+esm1
  • python3.7 Ubuntu Pro 18.04 LTS 3.7.5-2ubuntu1~18.04.2+esm3
  • python3.8 Ubuntu Pro 18.04 LTS 3.8.0-3ubuntu1~18.04.2+esm2

ubuntu advisories UBUNTU-CVE-2020-26116

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • python3 RHEL 8 3.6.8-37.el8
  • python3-idle RHEL 8 3.6.8-37.el8
  • python3-libs RHEL 8 3.6.8-37.el8
  • python3-test RHEL 8 3.6.8-37.el8
  • platform-python RHEL 8 3.6.8-37.el8
  • python3-tkinter RHEL 8 3.6.8-37.el8
  • python RHEL 7 2.7.5-92.el7_9
  • tkinter RHEL 7 2.7.5-92.el7_9

red hat advisories RHSA-2021:1633RHSA-2022:5235RHSA-2021:1761RHSA-2020:4299RHSA-2020:4285RHSA-2021:1879

  • python-urllib3 OpenStack Cloud Crowbar 8, OpenStack Cloud 8, HPE Helion OpenStack 8 1.22-5.15.1
  • python-urllib3 OpenStack Cloud 7 1.16-3.15.1
  • python-urllib3 OpenStack Cloud Crowbar 9, OpenStack Cloud 9 1.23-3.18.1
  • python-urllib3 SLES for SAP 15, SLES 15-LTSS, SLE High Performance Computing 15-LTSS +1 more 1.22-6.12.1
  • python-urllib3 SLES for SAP 12 SP5, SLES 12 SP5, SLE Workstation Extension 12 SP5 +3 more 1.22-3.23.1
  • python3 SLES for SAP 15, SLES 15-LTSS, SLE Module for Basesystem 15 SP2 +3 more 3.6.12-3.67.2
  • python3-core SLES for SAP 15, SLES 15-LTSS, SLE Module for Development Tools 15 SP2 +5 more 3.6.12-3.67.2
  • python36 SLES for SAP 12 SP5, SLES 12 SP5 3.6.12-4.22.2

suse advisories SUSE-SU-2021:0515-1SUSE-SU-2021:0486-1SUSE-SU-2021:0342-1SUSE-SU-2021:0341-1SUSE-SU-2021:0299-1SUSE-SU-2020:3930-1

  • python36 openSUSE Tumbleweed 3.6.15-1.1
  • python38 openSUSE Tumbleweed 3.8.12-1.2
  • python openSUSE Tumbleweed 2.7.18-9.1
  • python3 openSUSE Leap 15.1 3.6.12-lp151.6.32.1
  • python3-core openSUSE Leap 15.1 3.6.12-lp151.6.32.1
  • python3-documentation openSUSE Leap 15.1 3.6.12-lp151.6.32.1
  • python3 openSUSE Leap 15.2 3.6.12-lp152.4.14.1
  • python3-core openSUSE Leap 15.2 3.6.12-lp152.4.14.1

opensuse advisories openSUSE-SU-2024:11284-1openSUSE-SU-2024:11285-1openSUSE-SU-2024:11551-1openSUSE-SU-2020:2333-1openSUSE-SU-2020:2332-1openSUSE-SU-2020:1988-1

  • python38-ply AlmaLinux 8 3.11-10.module_el8.6.0+2778+cd494b30
  • python38-six AlmaLinux 8 1.12.0-10.module_el8.6.0+2778+cd494b30
  • python38-cffi AlmaLinux 8 1.13.2-3.module_el8.6.0+2778+cd494b30
  • python38-idna AlmaLinux 8 2.8-6.module_el8.6.0+2778+cd494b30
  • python38-pytz AlmaLinux 8 2019.3-3.module_el8.6.0+2778+cd494b30
  • python38-scipy AlmaLinux 8 1.3.1-4.module_el8.6.0+2778+cd494b30
  • python38-Cython AlmaLinux 8 0.29.14-4.module_el8.6.0+2778+cd494b30
  • python38-chardet AlmaLinux 8 3.0.4-19.module_el8.6.0+2778+cd494b30

almalinux advisories ALSA-2021:1879ALSA-2021:1761

  • pytz Rocky Linux 8 2019.3-3.module+el8.4.0+570+c2eaf144
  • babel Rocky Linux 8 2.7.0-10.module+el8.4.0+570+c2eaf144
  • numpy Rocky Linux 8 1.17.3-5.module+el8.4.0+570+c2eaf144
  • scipy Rocky Linux 8 1.3.1-4.module+el8.5.0+672+ab6eb015
  • scipy Rocky Linux 8 1.3.1-4.module+el8.4.0+570+c2eaf144
  • Cython Rocky Linux 8 0.29.14-4.module+el8.4.0+570+c2eaf144
  • PyYAML Rocky Linux 8 5.3.1-1.module+el8.4.0+570+c2eaf144
  • mod_wsgi Rocky Linux 8 4.6.8-3.module+el8.4.0+570+c2eaf144

rocky linux advisories RLSA-2021:1879RLSA-2021:1761

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2020-26116 updated cvss 6.5

python: CRLF injection via HTTP request method in httplib/http.client

  • Red Hat Enterprise Linux 5 python Red Hat Enterprise Linux 6 python, tkinter, python-libs, python-test, python-tools
    affected: no fix planned “Out of support scope”
  • Red Hat Enterprise Linux 7 python3, python3-idle, python3-libs, python3-test, python3-tkinter
    affected: no fix planned “Will not fix”
  • Red Hat Quay 3 quay
    affected: no fix available
  • Red Hat Enterprise Linux AppStream (v. 8) python3-idle 3.6.8-37.el8, python3-test 3.6.8-37.el8, platform-python 3.6.8-37.el8, python3-tkinter 3.6.8-37.el8, babel 2.5.1-9.module+el8.1.0+3111+de3f2d8e, pytz 2019.3-3.module+el8.4.0+8888+89bc7e79, +152 more
    fixed: vendor fix RHSA-2021:1761
  • Red Hat Enterprise Linux AppStream EUS (v. 8.2) python3-idle 3.6.8-24.el8_2, python3-test 3.6.8-24.el8_2, platform-python 3.6.8-24.el8_2, python3-tkinter 3.6.8-24.el8_2
    fixed: vendor fix RHSA-2021:3366
  • Red Hat Enterprise Linux BaseOS (v. 8) python3 3.6.8-37.el8, python3-libs 3.6.8-37.el8, python3-test 3.6.8-37.el8, platform-python 3.6.8-37.el8
    fixed: vendor fix RHSA-2021:1633
  • Red Hat Enterprise Linux BaseOS EUS (v. 8.2) python3 3.6.8-24.el8_2, python3-libs 3.6.8-24.el8_2, python3-test 3.6.8-24.el8_2, platform-python 3.6.8-24.el8_2
    fixed: vendor fix RHSA-2021:3366
  • Red Hat Enterprise Linux Client (v. 7) python 2.7.5-92.el7_9, python-libs 2.7.5-92.el7_9 Red Hat Enterprise Linux Client Optional (v. 7) tkinter 2.7.5-92.el7_9, python-test 2.7.5-92.el7_9, python-tools 2.7.5-92.el7_9 Red Hat Enterprise Linux ComputeNode Optional (v. 7) tkinter 2.7.5-92.el7_9, python-test 2.7.5-92.el7_9, python-tools 2.7.5-92.el7_9 Red Hat Enterprise Linux Server (v. 7) python 2.7.5-92.el7_9, python-libs 2.7.5-92.el7_9 Red Hat Enterprise Linux Server Optional (v. 7) tkinter 2.7.5-92.el7_9, python-test 2.7.5-92.el7_9, python-tools 2.7.5-92.el7_9 Red Hat Enterprise Linux Workstation (v. 7) python 2.7.5-92.el7_9, python-libs 2.7.5-92.el7_9
    +1 more products
    Red Hat Enterprise Linux Workstation Optional (v. 7) tkinter 2.7.5-92.el7_9, python-test 2.7.5-92.el7_9, python-tools 2.7.5-92.el7_9
    fixed: vendor fix RHSA-2022:5235
show 2 more
  • Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 6) rh-python36-python 3.6.12-1.el6, rh-python36-python-pip 9.0.1-5.el6, rh-python36-python-libs 3.6.12-1.el6, rh-python36-python-test 3.6.12-1.el6, rh-python36-python-tools 3.6.12-1.el6, rh-python36-python-tkinter 3.6.12-1.el6, +1 more Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 7) python27-python 2.7.18-2.el7, python27-tkinter 2.7.18-2.el7, rh-python38-python 3.8.6-1.el7, python27-python-pip 8.1.2-6.el7, rh-python36-python 3.6.12-1.el7, python27-python-libs 2.7.18-2.el7, +17 more Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.6) python27-python 2.7.18-2.el7, python27-tkinter 2.7.18-2.el7, rh-python38-python 3.8.6-1.el7, python27-python-pip 8.1.2-6.el7, rh-python36-python 3.6.12-1.el7, python27-python-libs 2.7.18-2.el7, +17 more Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.7) python27-python 2.7.18-2.el7, python27-tkinter 2.7.18-2.el7, rh-python38-python 3.8.6-1.el7, python27-python-pip 8.1.2-6.el7, rh-python36-python 3.6.12-1.el7, python27-python-libs 2.7.18-2.el7, +17 more Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 6) rh-python36-python 3.6.12-1.el6, rh-python36-python-pip 9.0.1-5.el6, rh-python36-python-libs 3.6.12-1.el6, rh-python36-python-test 3.6.12-1.el6, rh-python36-python-tools 3.6.12-1.el6, rh-python36-python-tkinter 3.6.12-1.el6, +1 more Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 7) python27-python 2.7.18-2.el7, python27-tkinter 2.7.18-2.el7, rh-python38-python 3.8.6-1.el7, python27-python-pip 8.1.2-6.el7, rh-python36-python 3.6.12-1.el7, python27-python-libs 2.7.18-2.el7, +17 more
    fixed: vendor fix RHSA-2020:4285
  • Red Hat Enterprise Linux 8 scipy, python36, python-nose, python-wheel, python3-bson, python3-nose, +19 more
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

cisa ICSA-23-348-10 updated cvss 7.2

Siemens SIMATIC S7-1500

  • Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) >= 3.1.0, < 3.1.5 Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) >= 3.1.0, < 3.1.5 Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) >= 3.1.0, < 3.1.5 Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0) >= 3.1.0, < 3.1.5 Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0) >= 3.1.0, < 3.1.5
    affected: fixed in V3.1.5, mitigation support.industry.siemens.com

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
31 d ago

Exploit prediction

6.36% chance of exploitation in the next 30 days, higher than 93% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • bugs.python.org https://bugs.python.org/issue39603 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 3.1 7.2 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
NVD 2.0 6.4 AV:N/AC:L/Au:N/C:P/I:P/A:N
OSV 3.1 7.2 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N

Affected packages

ecosystem package affected fixed in
bitnami libpython
>=3.0.0, <3.5.10
>=3.6.0, <3.6.12
>=3.7.0, <3.7.9
>=3.8.0, <3.8.5
3.5.10
3.6.12
3.7.9
3.8.5
bitnami python
>=3.0.0, <3.5.10
>=3.6.0, <3.6.12
>=3.7.0, <3.7.9
>=3.8.0, <3.8.5
3.5.10
3.6.12
3.7.9
3.8.5
bitnami python-min
>=3.0.0, <3.5.10
>=3.6.0, <3.6.12
>=3.7.0, <3.7.9
>=3.8.0, <3.8.5
3.5.10
3.6.12
3.7.9
3.8.5

Affected products

  • Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP
  • Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP
  • Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP

Classification

Weakness
  • CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.