Ubuntu USN · USN-8456-1

libxml2 vulnerability

Published: Mon, 22 Jun 2026 12:09

CVE-2026-6653

Summary

libxml2 could be made to crash or run programs if it received specially crafted input.

Details

Geoffrey Humphreys discovered that libxml2 had a use after free when parsing the internal subset of a DTD. A remote attacker could possibly use this issue to cause a denial of service or possibly execute arbitrary code.

Recommended actions per Ubuntu release

StackPatch playbook auto-generated per release codename and per affected package.

Ubuntu jammy

libxml2→2.9.13+dfsg-1ubuntu0.12apt_upgrade
Standard apt upgrade. Install 2.9.13+dfsg-1ubuntu0.12 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libxml2
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
libxml2→2.9.13+dfsg-1ubuntu0.12apt_upgrade
Standard apt upgrade. Install 2.9.13+dfsg-1ubuntu0.12 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libxml2
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
libxml2-dev→2.9.13+dfsg-1ubuntu0.12apt_upgrade
Standard apt upgrade. Install 2.9.13+dfsg-1ubuntu0.12 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libxml2-dev
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
libxml2-doc→2.9.13+dfsg-1ubuntu0.12apt_upgrade
Standard apt upgrade. Install 2.9.13+dfsg-1ubuntu0.12 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libxml2-doc
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
libxml2-utils→2.9.13+dfsg-1ubuntu0.12apt_upgrade
Standard apt upgrade. Install 2.9.13+dfsg-1ubuntu0.12 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libxml2-utils
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
python3-libxml2→2.9.13+dfsg-1ubuntu0.12apt_upgrade
Standard apt upgrade. Install 2.9.13+dfsg-1ubuntu0.12 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y python3-libxml2
```
Most apt upgrades restart their service automatically. needrestart lists anything else.

Ubuntu noble

libxml2→2.9.14+dfsg-1.3ubuntu3.8apt_upgrade
Standard apt upgrade. Install 2.9.14+dfsg-1.3ubuntu3.8 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libxml2
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
libxml2→2.9.14+dfsg-1.3ubuntu3.8apt_upgrade
Standard apt upgrade. Install 2.9.14+dfsg-1.3ubuntu3.8 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libxml2
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
libxml2-dev→2.9.14+dfsg-1.3ubuntu3.8apt_upgrade
Standard apt upgrade. Install 2.9.14+dfsg-1.3ubuntu3.8 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libxml2-dev
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
libxml2-doc→2.9.14+dfsg-1.3ubuntu3.8apt_upgrade
Standard apt upgrade. Install 2.9.14+dfsg-1.3ubuntu3.8 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libxml2-doc
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
libxml2-utils→2.9.14+dfsg-1.3ubuntu3.8apt_upgrade
Standard apt upgrade. Install 2.9.14+dfsg-1.3ubuntu3.8 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libxml2-utils
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
python3-libxml2→2.9.14+dfsg-1.3ubuntu3.8apt_upgrade
Standard apt upgrade. Install 2.9.14+dfsg-1.3ubuntu3.8 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y python3-libxml2
```
Most apt upgrades restart their service automatically. needrestart lists anything else.

Are YOU affected by USN-8456-1?

5-second check on your actual server. Reads /etc/os-release, uname -r, and dpkg-query; matches against the live USN + Debian Security Tracker feeds; tells you whether USN-8456-1 (and any other live CVE) applies. Anonymous, no signup.

curl https://mindsparkstack.com/scan.sh | bash

Form-based quickscan Read the bash source first

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