CVE-2026-6732: A flaw was found in libxml2

This month

MEDIUM 6.5WATCHLISTUPGRADEMITIGATEMITIGATE

CVE-2026-6732 is a medium-severity flaw (CVSS 6.5) affecting libxml2, hardened images, jboss core services. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

A flaw was found in libxml2. This vulnerability occurs when the library processes a specially crafted XML Schema Definition (XSD) validated document that includes an internal entity reference. An attacker could exploit this by providing a malicious document, leading to a type confusion error that causes the application to crash. This results in a denial of service (DoS), making the affected system or application unavailable.

Why this priority

Public exploit reference
On your watchlist

A fixed release or distro patch exists.

Risk facts

CVSS score	6.5 (Medium)
Attack vector	Adjacent network
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.6% (top 50%)
CISA exploited list	No
Weakness	CWE-843
Published	2026-04-23
Last modified	2026-10-26

Publisher (CNA): Red Hat, Inc. · Vendor: ibm · redhat · xmlsoft

Last updated 2026-10-26 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-04-23 23:16 UTCPublished CVE record published
2026-10-26 21:10 UTCUpdated Record last modified

xmlsoft libxml2 UPGRADE

Affected: >= 2.13.0 and < 2.15.3

Fixed in: 2.15.3

Safe to downgrade to: a release before 2.13.0

1. Check installed version

apt-cache policy libxml2 || rpm -q libxml2 || libxml2 --version

2. UPGRADE to 2.15.3 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade libxml2

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade libxml2

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 2.13.0 (Debian / Ubuntu)

apt-cache madison libxml2 sudo apt install libxml2=<VERSION_BEFORE_2.13.0> sudo apt-mark hold libxml2

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list libxml2 sudo dnf downgrade libxml2-<VERSION_BEFORE_2.13.0> sudo dnf versionlock add libxml2

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

redhat hardened images MITIGATE

Affected: all versions

Fixed in: no fixed release known

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy hardened-images || rpm -q hardened-images || hardened-images --version

No fixed or unaffected release known

Apply the vendor mitigation from the advisory, disable the affected feature, or restrict network access.

redhat jboss core services MITIGATE

Affected: all versions

Fixed in: no fixed release known

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy jboss-core-services || rpm -q jboss-core-services || jboss-core-services --version

No fixed or unaffected release known

Apply the vendor mitigation from the advisory, disable the affected feature, or restrict network access.

redhat openshift container platform DOWNGRADE

Affected: 4.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 4.0

1. Check installed version

apt-cache policy openshift-container-platform || rpm -q openshift-container-platform || openshift-container-platform --version

2. No fixed release: DOWNGRADE to a release before 4.0 (Debian / Ubuntu)

apt-cache madison openshift-container-platform sudo apt install openshift-container-platform=<VERSION_BEFORE_4.0> sudo apt-mark hold openshift-container-platform

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list openshift-container-platform sudo dnf downgrade openshift-container-platform-<VERSION_BEFORE_4.0> sudo dnf versionlock add openshift-container-platform

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

redhat enterprise linux MITIGATE

Affected: 6.0 · 7.0 · 8.0 · 9.0 · 10.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 6.0

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

ibm vios UPGRADE

Affected: >= 4.1.0 and < 4.1.1.30 · 4.1.2.0

Fixed in: 4.1.1.30

Safe to downgrade to: a release before 4.1.0

1. Check installed version

apt-cache policy vios || rpm -q vios || vios --version

2. UPGRADE to 4.1.1.30 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade vios

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade vios

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 4.1.0 (Debian / Ubuntu)

apt-cache madison vios sudo apt install vios=<VERSION_BEFORE_4.1.0> sudo apt-mark hold vios

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list vios sudo dnf downgrade vios-<VERSION_BEFORE_4.1.0> sudo dnf versionlock add vios

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-6732?

libxml2: upgrade to 2.15.3; hardened images: mitigate or apply the listed mitigation; jboss core services: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2026-6732 being exploited?

CVE-2026-6732 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-6732 affect?

CVE-2026-6732 affects libxml2, hardened images, jboss core services. Severity is medium (CVSS 6.5). A flaw was found in libxml2. This vulnerability occurs when the library processes a specially crafted XML Schema Definition (XSD) validated document that includes an internal entity reference. An attacker could exploit this by providing a m

How urgent is CVE-2026-6732?

Priority 45/100. Public exploit reference; On your watchlist

Software pages

JBoss and WildFly vulnerabilities · Red Hat OpenShift vulnerabilities · libxml2 vulnerabilities

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References

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