Reference page — cumulative record through Monday, October 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2017-9233

CVE-2017-9233HIGH

n/a n/a — XML External Entity vulnerability in libexpat 2.2.0 and earlier (Expat XML Parser Library) allows attackers to put the parser in an infin…

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   N   L   N   N  U  N  N  H    7.5   .0874   95.1     —

AFFECTED
  Product  Versions  Fixed
  n/a      n/a –     —

TIMELINE
  May 26  Reserved by mitre
  Jul 25  Published (CNA: mitre)
  Oct 8   ENRICHED — CVE-2017-9233. Received CVSS 7.5 and CPE data from NVD.
  Oct 8   EXPLOIT PUBLISHED — CVE-2017-9233. Public exploit reference added.

CWE-611, CWE-835 · CNA: mitre · CVSS v3.1 · 13 references · NVD status: Modified

Description

XML External Entity vulnerability in libexpat 2.2.0 and earlier (Expat XML Parser Library) allows attackers to put the parser in an infinite loop using a malformed external entity definition from an external DTD.

Lifecycle

Complete event history — 4 events, chronological
Date	Event	Detail
May 26, 2017	Reserved	Reserved by mitre
July 25, 2017	Published	Published (CNA: mitre)
October 8, 2026	ENRICHED	ENRICHED — CVE-2017-9233. Received CVSS 7.5 and CPE data from NVD.
October 8, 2026	EXPLOIT PUBLISHED	EXPLOIT PUBLISHED — CVE-2017-9233. Public exploit reference added.

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
n/a	n/a	—	n/a	—

Weaknesses

CWE-611 · CWE-835

References (13)

http://www.debian.org/security/2017/dsa-3898 [Third Party Advisory]
http://www.openwall.com/lists/oss-security/2017/06/17/7 [Mailing List, VDB Entry]
http://www.securityfocus.com/bid/99276 [Third Party Advisory, VDB Entry]
http://www.securitytracker.com/id/1039427 [Third Party Advisory, VDB Entry]
https://github.com/libexpat/libexpat/blob/master/expat/Changes [Release Notes, Third Party Advisory]
https://libexpat.github.io/doc/cve-2017-9233/ [Exploit, Technical Description, Vendor Advisory]
https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3E
https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3E
https://support.apple.com/HT208112 [Third Party Advisory]
https://support.apple.com/HT208113 [Third Party Advisory]
https://support.apple.com/HT208115 [Third Party Advisory]
https://support.apple.com/HT208144 [Third Party Advisory]
https://support.f5.com/csp/article/K03244804 [Third Party Advisory]

Authoritative record: CVE-2017-9233 at cve.org

Weaknesses: CWE-611 · CWE-835

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2017-9233 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 Monday, October 19, 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.