Reference page — cumulative record through Thursday, October 8, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2018-14647

CVE-2018-14647HIGH

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

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   N   L   N   N  U  N  N  H    7.5   .1091   95.8     —

AFFECTED
  Product  Versions                        Fixed
  Python   3.8, 3.7, 3.6, 3.5, 3.4, 2.7 –  —

TIMELINE
  Jul 27  Reserved by redhat
  Sep 25  Published (CNA: redhat)
  Oct 7   RESCORED — CVE-2018-14647 (The Python Project Python). CVSS 5.3 → 7.5 (NVD).

CWE-909, CWE-335, CWE-665 · CNA: redhat · CVSS v3.1 · 16 references · NVD status: Modified

Description

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.

Lifecycle

Complete event history — 3 events, chronological
Date	Event	Detail
July 27, 2018	Reserved	Reserved by redhat
September 25, 2018	Published	Published (CNA: redhat)
October 7, 2026	RESCORED	RESCORED — CVE-2018-14647 (The Python Project Python). CVSS 5.3 → 7.5 (NVD).

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
The Python Project	Python	—	3.8, 3.7, 3.6, 3.5, 3.4, 2.7	—

Weaknesses

CWE-909 · CWE-335 · CWE-665

References (16)

http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00040.html [Mailing List, Third Party Advisory]
http://www.securityfocus.com/bid/105396 [Third Party Advisory, VDB Entry]
http://www.securitytracker.com/id/1041740 [Third Party Advisory, VDB Entry]
https://access.redhat.com/errata/RHSA-2019:1260 [Third Party Advisory]
https://access.redhat.com/errata/RHSA-2019:2030 [Third Party Advisory]
https://access.redhat.com/errata/RHSA-2019:3725 [Third Party Advisory]
https://bugs.python.org/issue34623 [Issue Tracking, Patch, Vendor Advisory]
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-14647 [Issue Tracking, Third Party Advisory]
https://lists.apache.org/thread.html/r1b103833cb5bc8466e24ff0ecc5e75b45a705334ab6a444e64e840a0%40%3Cissues.bookkeeper.apache.org%3E
https://lists.debian.org/debian-lts-announce/2019/06/msg00022.html [Mailing List, Third Party Advisory]
https://lists.debian.org/debian-lts-announce/2019/06/msg00023.html [Mailing List, Third Party Advisory]
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RBJCB2HWOJLP3L7CUQHJHNBHLSVOXJE5/
https://usn.ubuntu.com/3817-1/ [Third Party Advisory]
https://usn.ubuntu.com/3817-2/ [Third Party Advisory]
https://www.debian.org/security/2018/dsa-4306 [Third Party Advisory]
https://www.debian.org/security/2018/dsa-4307 [Third Party Advisory]

Authoritative record: CVE-2018-14647 at cve.org

Vendors: the python project

Weaknesses: CWE-909 · CWE-335 · CWE-665

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2018-14647 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Thursday, October 8, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.