CVE-2026-4739

Description

Integer Overflow or Wraparound vulnerability in InsightSoftwareConsortium ITK (‎Modules/ThirdParty/Expat/src/expat modules).This issue affects ITK: before 2.7.1.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
expat	26.04 LTS resolute	Not affected
	25.10 questing	Ignored end of life, was needs-triage
	24.04 LTS noble	Not affected
	22.04 LTS jammy	Not affected
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
	14.04 LTS trusty	Not affected
apache2	26.04 LTS resolute	Not affected
	25.10 questing	Not affected
	24.04 LTS noble	Not affected
	22.04 LTS jammy	Not affected
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
	14.04 LTS trusty	Not affected
apr-util	26.04 LTS resolute	Not affected
	25.10 questing	Not affected
	24.04 LTS noble	Not affected
	22.04 LTS jammy	Not affected
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
	14.04 LTS trusty	Not affected
cmake	26.04 LTS resolute	Not affected
	25.10 questing	Not affected
	24.04 LTS noble	Not affected
	22.04 LTS jammy	Not affected
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
ghostscript	26.04 LTS resolute	Not affected
	25.10 questing	Not affected
	24.04 LTS noble	Not affected
	22.04 LTS jammy	Not affected
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
texlive-bin	26.04 LTS resolute	Not affected
	25.10 questing	Not affected
	24.04 LTS noble	Not affected
	22.04 LTS jammy	Not affected
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
xmlrpc-c	26.04 LTS resolute	Not affected
	25.10 questing	Ignored end of life, was needs-triage
	24.04 LTS noble	Not affected
	22.04 LTS jammy	Not affected
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
	14.04 LTS trusty	Not affected
vnc4	26.04 LTS resolute	Not in release
	25.10 questing	Not in release
	24.04 LTS noble	Not in release
	22.04 LTS jammy	Not in release
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
	14.04 LTS trusty	Not affected
wbxml2	26.04 LTS resolute	Not affected
	25.10 questing	Ignored end of life, was needs-triage
	24.04 LTS noble	Not affected
	22.04 LTS jammy	Not affected
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
swish-e	26.04 LTS resolute	Not affected
	25.10 questing	Ignored end of life, was needs-triage
	24.04 LTS noble	Not affected
	22.04 LTS jammy	Not affected
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
insighttoolkit4	26.04 LTS resolute	Not in release
	25.10 questing	Not in release
	24.04 LTS noble	Not in release
	22.04 LTS jammy	Not affected
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
cadaver	26.04 LTS resolute	Not affected
	25.10 questing	Ignored end of life, was needs-triage
	24.04 LTS noble	Not affected
	22.04 LTS jammy	Not affected
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
gdcm	26.04 LTS resolute	Not affected
	25.10 questing	Not affected
	24.04 LTS noble	Not affected
	22.04 LTS jammy	Not affected
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
	14.04 LTS trusty	Not affected
ayttm	26.04 LTS resolute	Not in release
	25.10 questing	Not in release
	24.04 LTS noble	Not in release
	22.04 LTS jammy	Not in release
	16.04 LTS xenial	Not affected
cableswig	26.04 LTS resolute	Not in release
	25.10 questing	Not in release
	24.04 LTS noble	Not in release
	22.04 LTS jammy	Not in release
	16.04 LTS xenial	Not affected
coin3	26.04 LTS resolute	Not affected
	25.10 questing	Not affected
	24.04 LTS noble	Not affected
	22.04 LTS jammy	Not affected
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
	14.04 LTS trusty	Not affected
matanza	26.04 LTS resolute	Ignored
	25.10 questing	Ignored
	24.04 LTS noble	Ignored
	22.04 LTS jammy	Ignored
	20.04 LTS focal	Ignored
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
tdom	26.04 LTS resolute	Not affected
	25.10 questing	Ignored end of life, was needs-triage
	24.04 LTS noble	Not affected
	22.04 LTS jammy	Not affected
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
vtk	26.04 LTS resolute	Not in release
	25.10 questing	Not in release
	24.04 LTS noble	Not in release
	22.04 LTS jammy	Not in release
	16.04 LTS xenial	Not affected
	14.04 LTS trusty	Not affected
smart	26.04 LTS resolute	Not in release
	25.10 questing	Not in release
	24.04 LTS noble	Not in release
	22.04 LTS jammy	Not in release
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
firefox	26.04 LTS resolute	Not affected
	25.10 questing	Not affected
	24.04 LTS noble	Not affected
	22.04 LTS jammy	Not affected
thunderbird	26.04 LTS resolute	Not affected
	25.10 questing	Not affected
	24.04 LTS noble	Not affected
	22.04 LTS jammy	Not affected
libxmltok	26.04 LTS resolute	Not in release
	25.10 questing	Not in release
	24.04 LTS noble	Not affected
	22.04 LTS jammy	Not affected
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected

Notes

sbeattie

paraview uses system expat xotcl uses system expat poco uses system expat gdcm uses system expat audacity uses system expat simgear uses system expat coin3 uses system expat as of 4.0.0~CMake~6f54f1602475+ds1-1 sitecopy uses system expat since 1:0.16.0-1 (dapper!) insighttoolkit uses system expat as of 4.12.1-dfsg1

mdeslaur

apache2 uses system expat apr-util uses system expat cmake uses system expat ghostscript uses system expat firefox uses system expat thunderbird uses system expat matanza embeds an expat fork to parse its own config file, there is no attack vector there, we will not be fixing matanza.

igcontreras

this is not an expat vulnerability

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
insighttoolkit4	Upstream: 38cca37

Severity score breakdown

CVSS version: CVSS v4.0

Base score 9.4 · Critical

Base metrics

Parameter	Value
Attack vector	Network
Attack complexity	Low
Attack requirements	None
Privileges required	None
User interaction	Passive
Vulnerable system - Confidentiality impact	High
Vulnerable system - Integrity impact	High
Vulnerable system - Availability impact	High
Subsequent system - Confidentiality impact	High
Subsequent system - Integrity impact	High
Subsequent system - Availability impact	High

Scores

Parameter	Value
Base score	9.4 · Critical
Base + Threat score	-
Base + Environmental score	-
Base + Threat + Environmental score	-

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:A/S:P/AU:Y/R:U/V:C/RE:M/U:Amber