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-2016-9063

CVE-2016-9063CRITICAL

Mozilla Firefox — An integer overflow during the parsing of XML using the Expat library.

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   N   L   N   N  U  H  H  H    9.8   .0536   92.6     —

AFFECTED
  Product  Versions       Fixed
  Firefox  unspecified –  —

TIMELINE
  Oct 27  Reserved by mozilla
  Jun 11  Published (CNA: mozilla)
  Oct 8   ENRICHED — CVE-2016-9063 (Mozilla Firefox). Received CVSS 9.8 and CPE data from NVD.

CWE-190 · CNA: mozilla · CVSS v3.1 · 6 references · NVD status: Modified

Description

An integer overflow during the parsing of XML using the Expat library. This vulnerability affects Firefox < 50.

Lifecycle

Complete event history — 3 events, chronological
Date	Event	Detail
October 27, 2016	Reserved	Reserved by mozilla
June 11, 2018	Published	Published (CNA: mozilla)
October 8, 2026	ENRICHED	ENRICHED — CVE-2016-9063 (Mozilla Firefox). Received CVSS 9.8 and CPE data from NVD.

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
Mozilla	Firefox	—	unspecified	—

Weaknesses

CWE-190

References (6)

http://www.securityfocus.com/bid/94337 [Third Party Advisory, VDB Entry]
http://www.securitytracker.com/id/1037298 [Third Party Advisory, VDB Entry]
http://www.securitytracker.com/id/1039427 [Third Party Advisory, VDB Entry]
https://bugzilla.mozilla.org/show_bug.cgi?id=1274777 [Issue Tracking, Vendor Advisory]
https://www.debian.org/security/2017/dsa-3898 [Third Party Advisory]
https://www.mozilla.org/security/advisories/mfsa2016-89/ [Vendor Advisory]

Authoritative record: CVE-2016-9063 at cve.org

Vendors: mozilla

Weaknesses: CWE-190

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2016-9063 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.