Skip to content
Fencer Vulns
medium 5.3

CVE-2018-14647 json

Python's elementtree C accelerator failed to initialise Expat's hash salt during initialization.

published 2018-09-25 8 y ago modified 2026-10-07 32 d ago also EUVD-2018-6545

cvss
5.3
version 3.0, CNA
cisa kev
Not listed
not in CISA's catalog
epss
10.9%
EPSS 10.9% chance of exploitation in 30 days, percentile 95%
public exploits
0
none known

Summary

Python's elementtree C accelerator failed to initialise Expat's hash salt during initialization. This could make it easy to conduct denial of service attacks against Expat by constructing an XML document that would cause pathological hash collisions in Expat's internal data structures, consuming large amounts CPU and RAM. The vulnerability exists in Python versions 3.7.0, 3.6.0 through 3.6.6, 3.5.0 through 3.5.6, 3.4.0 through 3.4.9, 2.7.0 through 2.7.15.

Patch / fix

  • python2.7 Debian 11 2.7.15-5

debian advisories DEBIAN-CVE-2018-14647

  • python2.7 Ubuntu 14.04 LTS 2.7.6-8ubuntu0.5
  • python2.7 Ubuntu 16.04 LTS 2.7.12-1ubuntu0~16.04.4
  • python2.7 Ubuntu 18.04 LTS 2.7.15~rc1-1ubuntu0.1
  • python3.4 Ubuntu 14.04 LTS 3.4.3-1ubuntu1~14.04.7
  • python3.5 Ubuntu 16.04 LTS 3.5.2-2ubuntu0~16.04.5
  • python3.6 Ubuntu 18.04 LTS 3.6.7-1~18.04
  • python3.7 Ubuntu 18.04 LTS 3.7.1-1~18.04
  • python3.5 Ubuntu Pro 14.04 LTS 3.5.2-2ubuntu0~16.04.4~14.04.1+esm1

ubuntu advisories UBUNTU-CVE-2018-14647

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

  • rh-python36-python RHEL 3 SOFTWARE_COLLECTIONS 3.6.9-2.el6
  • rh-python36-python RHEL 3 SOFTWARE_COLLECTIONS 3.6.9-2.el7
  • rh-python36-python-libs RHEL 3 SOFTWARE_COLLECTIONS 3.6.9-2.el6
  • rh-python36-python-libs RHEL 3 SOFTWARE_COLLECTIONS 3.6.9-2.el7
  • rh-python36-python-test RHEL 3 SOFTWARE_COLLECTIONS 3.6.9-2.el6
  • rh-python36-python-test RHEL 3 SOFTWARE_COLLECTIONS 3.6.9-2.el7
  • rh-python36-python-tools RHEL 3 SOFTWARE_COLLECTIONS 3.6.9-2.el6
  • rh-python36-python-tools RHEL 3 SOFTWARE_COLLECTIONS 3.6.9-2.el7

red hat advisories RHSA-2020:1462RHSA-2020:1346RHSA-2019:3725RHSA-2020:1268RHSA-2019:2030RHSA-2019:1260

  • python3 SLES for SAP 12 SP5, SLES for SAP 12 SP4, SLES for SAP 12 SP3 +16 more 3.4.10-25.52.1
  • python3-base SLES for SAP 12 SP5, SLES for SAP 12 SP4, SLES for SAP 12 SP3 +16 more 3.4.10-25.52.1
  • python SLE Module for Python 2 15 SP1, SLE Module for Desktop Applications 15 SP1, SLE Module for Desktop Applications 15 +2 more 2.7.17-7.32.2
  • python-base SLE Module for Python 2 15 SP1, SLE Module for Basesystem 15 SP1, SLE Module for Basesystem 15 2.7.17-7.32.1
  • python3 SLE Module for Basesystem 15 SP1, SLE Module for Basesystem 15 3.6.10-3.42.2
  • python3-base SLE Module for Development Tools 15 SP1, SLE Module for Development Tools 15, SLE Module for Basesystem 15 SP1 +1 more 3.6.10-3.42.2
  • python3 SLES 12 SP4, SLES 12 SP3-BCL, SLES 12 SP2-BCL +16 more 3.4.6-25.29.1
  • python3-base SLES 12 SP4, SLES 12 SP3-BCL, SLES 12 SP2-BCL +16 more 3.4.6-25.29.1

suse advisories SUSE-SU-2020:2699-1SUSE-SU-2020:0234-1SUSE-SU-2020:0114-1SUSE-SU-2019:2053-1SUSE-SU-2019:2053-2SUSE-SU-2019:0482-2

  • python openSUSE Tumbleweed 2.7.18-8.1
  • python36 openSUSE Tumbleweed 3.6.15-1.1
  • python3 openSUSE Leap 15.1 3.6.10-lp151.6.7.1
  • python3-base openSUSE Leap 15.1 3.6.10-lp151.6.7.1

opensuse advisories openSUSE-SU-2024:11202-1openSUSE-SU-2024:11284-1openSUSE-SU-2020:0086-1

  • python2 Alpine 3.15, Alpine 3.14, Alpine 3.13 +4 more 2.7.16-r0
  • python2 Alpine 3.8, Alpine 3.7 2.7.15-r2
  • python3 Alpine 3.8, Alpine 3.7, Alpine 3.6 3.6.8-r0
  • python2-tkinter Alpine 3.11, Alpine 3.10 2.7.16-r0

alpine advisories ALPINE-CVE-2018-14647

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

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-2018-14647 updated cvss 5.3

python: Missing salt initialization in _elementtree.c module

  • Red Hat Enterprise Linux 5 python Red Hat Enterprise Linux 6 python, tkinter, python-libs, python-test, python-tools Red Hat Software Collections rh-python35-python, rh-python35-python-libs, rh-python35-python-test, rh-python35-python-tools, rh-python35-python-tkinter
    affected: no fix planned “Will not fix”
  • Red Hat Ansible Tower 3.4 for RHEL 7 Server ansible-tower-34/ansible-tower-memcached 1.4.15-28, ansible-tower-35/ansible-tower-memcached 1.4.15-28, ansible-tower-37/ansible-tower-memcached-rhel7 1.4.15-28
    fixed: vendor fix RHBA-2020:0547
  • Red Hat Enterprise Linux Client (v. 7) python 2.7.5-86.el7, python-libs 2.7.5-86.el7 Red Hat Enterprise Linux Client Optional (v. 7) tkinter 2.7.5-86.el7, python-test 2.7.5-86.el7, python-tools 2.7.5-86.el7 Red Hat Enterprise Linux ComputeNode (v. 7) python 2.7.5-86.el7, python-libs 2.7.5-86.el7
    fixed: vendor fix RHSA-2019:2030
  • Red Hat Enterprise Linux ComputeNode EUS (v. 7.5) python 2.7.5-74.el7_5, python-libs 2.7.5-74.el7_5
    fixed: vendor fix RHSA-2020:1268
  • Red Hat Enterprise Linux ComputeNode EUS (v. 7.6) python 2.7.5-83.el7_6, python-libs 2.7.5-83.el7_6
    fixed: vendor fix RHSA-2020:1462
  • Red Hat Enterprise Linux ComputeNode Optional (v. 7) tkinter 2.7.5-86.el7, python-test 2.7.5-86.el7, python-tools 2.7.5-86.el7
    fixed: vendor fix RHSA-2019:2030
  • Red Hat Enterprise Linux ComputeNode Optional EUS (v. 7.5) tkinter 2.7.5-74.el7_5, python-test 2.7.5-74.el7_5, python-tools 2.7.5-74.el7_5
    fixed: vendor fix RHSA-2020:1268
  • Red Hat Enterprise Linux ComputeNode Optional EUS (v. 7.6) tkinter 2.7.5-83.el7_6, python-test 2.7.5-83.el7_6, python-tools 2.7.5-83.el7_6 Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server (v. 7) python 2.7.5-83.el7_6, python-libs 2.7.5-83.el7_6 Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server Optional (v. 7) tkinter 2.7.5-83.el7_6, python-test 2.7.5-83.el7_6, python-tools 2.7.5-83.el7_6
    fixed: vendor fix RHSA-2020:1462
show 14 more
  • Red Hat Enterprise Linux Server (v. 7) python 2.7.5-86.el7, python-libs 2.7.5-86.el7
    fixed: vendor fix RHSA-2019:2030
  • Red Hat Enterprise Linux Server AUS (v. 7.4) python 2.7.5-63.el7_4, python-libs 2.7.5-63.el7_4 Red Hat Enterprise Linux Server E4S (v. 7.4) python 2.7.5-63.el7_4, python-libs 2.7.5-63.el7_4
    fixed: vendor fix RHSA-2020:1346
  • Red Hat Enterprise Linux Server EUS (v. 7.5) python 2.7.5-74.el7_5, python-libs 2.7.5-74.el7_5
    fixed: vendor fix RHSA-2020:1268
  • Red Hat Enterprise Linux Server EUS (v. 7.6) python 2.7.5-83.el7_6, python-libs 2.7.5-83.el7_6
    fixed: vendor fix RHSA-2020:1462
  • Red Hat Enterprise Linux Server Optional (v. 7) tkinter 2.7.5-86.el7, python-test 2.7.5-86.el7, python-tools 2.7.5-86.el7
    fixed: vendor fix RHSA-2019:2030
  • Red Hat Enterprise Linux Server Optional AUS (v. 7.4) tkinter 2.7.5-63.el7_4, python-test 2.7.5-63.el7_4, python-tools 2.7.5-63.el7_4 Red Hat Enterprise Linux Server Optional E4S (v. 7.4) tkinter 2.7.5-63.el7_4, python-test 2.7.5-63.el7_4, python-tools 2.7.5-63.el7_4
    fixed: vendor fix RHSA-2020:1346
  • Red Hat Enterprise Linux Server Optional EUS (v. 7.5) tkinter 2.7.5-74.el7_5, python-test 2.7.5-74.el7_5, python-tools 2.7.5-74.el7_5
    fixed: vendor fix RHSA-2020:1268
  • Red Hat Enterprise Linux Server Optional EUS (v. 7.6) tkinter 2.7.5-83.el7_6, python-test 2.7.5-83.el7_6, python-tools 2.7.5-83.el7_6
    fixed: vendor fix RHSA-2020:1462
  • Red Hat Enterprise Linux Server Optional TUS (v. 7.4) tkinter 2.7.5-63.el7_4, python-test 2.7.5-63.el7_4, python-tools 2.7.5-63.el7_4 Red Hat Enterprise Linux Server TUS (v. 7.4) python 2.7.5-63.el7_4, python-libs 2.7.5-63.el7_4
    fixed: vendor fix RHSA-2020:1346
  • Red Hat Enterprise Linux Workstation (v. 7) python 2.7.5-86.el7, python-libs 2.7.5-86.el7 Red Hat Enterprise Linux Workstation Optional (v. 7) tkinter 2.7.5-86.el7, python-test 2.7.5-86.el7, python-tools 2.7.5-86.el7
    fixed: vendor fix RHSA-2019:2030
  • Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 6) python27-python 2.7.16-4.el6, python27-tkinter 2.7.16-4.el6, rh-python36-python 3.6.9-2.el6, python27-python-jinja2 2.6-12.el6, python27-python-libs 2.7.16-4.el6, python27-python-test 2.7.16-4.el6, +5 more Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 7) python27-python 2.7.16-4.el7, python27-tkinter 2.7.16-4.el7, rh-python36-python 3.6.9-2.el7, python27-python-jinja2 2.6-15.el7, python27-python-libs 2.7.16-4.el7, python27-python-test 2.7.16-4.el7, +5 more Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.4) python27-python 2.7.16-4.el7, python27-tkinter 2.7.16-4.el7, python27-python-jinja2 2.6-15.el7, python27-python-libs 2.7.16-4.el7, python27-python-test 2.7.16-4.el7, python27-python-tools 2.7.16-4.el7 Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.5) python27-python 2.7.16-4.el7, python27-tkinter 2.7.16-4.el7, rh-python36-python 3.6.9-2.el7, python27-python-jinja2 2.6-15.el7, python27-python-libs 2.7.16-4.el7, python27-python-test 2.7.16-4.el7, +5 more Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.6) python27-python 2.7.16-4.el7, python27-tkinter 2.7.16-4.el7, rh-python36-python 3.6.9-2.el7, python27-python-jinja2 2.6-15.el7, python27-python-libs 2.7.16-4.el7, python27-python-test 2.7.16-4.el7, +5 more
    fixed: vendor fix RHSA-2019:1260
  • Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.7) rh-python36-python 3.6.9-2.el7, rh-python36-python-libs 3.6.9-2.el7, rh-python36-python-test 3.6.9-2.el7, rh-python36-python-tools 3.6.9-2.el7, rh-python36-python-tkinter 3.6.9-2.el7
    fixed: vendor fix RHSA-2019:3725
  • Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 6) python27-python 2.7.16-4.el6, python27-tkinter 2.7.16-4.el6, rh-python36-python 3.6.9-2.el6, python27-python-jinja2 2.6-12.el6, python27-python-libs 2.7.16-4.el6, python27-python-test 2.7.16-4.el6, +5 more Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 7) python27-python 2.7.16-4.el7, python27-tkinter 2.7.16-4.el7, rh-python36-python 3.6.9-2.el7, python27-python-jinja2 2.6-15.el7, python27-python-libs 2.7.16-4.el7, python27-python-test 2.7.16-4.el7, +5 more
    fixed: vendor fix RHSA-2019:1260
  • Red Hat Enterprise Linux 8 scipy, python2, python3, python36, python-nose, python-wheel, +30 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 SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
32 d ago

Exploit prediction

10.91% chance of exploitation in the next 30 days, higher than 95% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.0 5.3 CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
NVD 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD 2.0 5.0 AV:N/AC:L/Au:N/C:N/I:N/A:P

Affected products

  • The Python Project Python

Classification

Weakness
  • CWE-665 Improper Initialization
  • CWE-335 Incorrect Usage of Seeds in Pseudo-Random Number Generator (PRNG)
  • CWE-909 Missing Initialization of Resource

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.