Description
A flaw was found in libxml2. Exponential entity expansion attack its possible bypassing all existing protection mechanisms and leading to denial of service.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| — | libxml2 | 2.9.11 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | libxml2 | 2.9.10+dfsg-6.7 | — |
| Debian 13 | libxml2 | 2.9.10+dfsg-6.7 | — |
| Debian 12 | libxml2 | 2.9.10+dfsg-6.7 | — |
| Debian 9 | libxml2 | 2.9.4+dfsg1-2.2+deb9u5 | DLA-2669-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | libxml2 | 2.9.10+dfsg-5ubuntu0.20.04.1 | USN-4991-1 |
| Ubuntu 18.04 LTS | libxml2 | 2.9.4+dfsg1-6.1ubuntu1.4 | USN-4991-1 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 16.04 LTS | libxml2 | 2.9.3+dfsg1-1ubuntu0.7+esm1 | USN-4991-1 |
| Ubuntu Pro 14.04 LTS | libxml2 | 2.9.1+dfsg1-3ubuntu4.13+esm2 | USN-4991-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8 | libxml2 +2 | 2.9.7-9.el8_4.2 | RHSA-2021:2569 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat JBoss Core Services 1 | jbcs-httpd24-apr-util +8 | 1.6.1-91.el8jbcs | RHSA-2022:1389 |
| Red Hat JBoss Core Services 1 | jbcs-httpd24-curl +2 | 7.78.0-3.el8jbcs | RHSA-2022:1389 |
| Red Hat JBoss Core Services 1 | jbcs-httpd24-httpd +6 | 2.4.37-80.el8jbcs | RHSA-2022:1389 |
| Red Hat JBoss Core Services 1 | jbcs-httpd24-mod_cluster-native | 1.3.16-10.Final_redhat_2.el8jbcs | RHSA-2022:1389 |
| Red Hat JBoss Core Services 1 | jbcs-httpd24-mod_http2 | 1.15.7-22.el8jbcs | RHSA-2022:1389 |
| Red Hat JBoss Core Services 1 | jbcs-httpd24-mod_jk +2 | 1.2.48-29.redhat_1.el8jbcs | RHSA-2022:1389 |
| Red Hat JBoss Core Services 1 | jbcs-httpd24-mod_md | 1:2.0.8-41.el8jbcs | RHSA-2022:1389 |
| Red Hat JBoss Core Services 1 | jbcs-httpd24-mod_security | 2.9.2-68.GA.el8jbcs | RHSA-2022:1389 |
| Red Hat JBoss Core Services 1 | jbcs-httpd24-mod_ssl +1 | 1:2.4.37-80.el8jbcs | RHSA-2022:1389 |
| Red Hat JBoss Core Services 1 | jbcs-httpd24-nghttp2 +1 | 1.39.2-41.el8jbcs | RHSA-2022:1389 |
| Red Hat JBoss Core Services 1 | jbcs-httpd24-openssl +4 | 1:1.1.1g-11.el8jbcs | RHSA-2022:1389 |
| Red Hat JBoss Core Services 1 | jbcs-httpd24-openssl-chil | 1.0.0-11.el8jbcs | RHSA-2022:1389 |
| Red Hat JBoss Core Services 1 | jbcs-httpd24-openssl-pkcs11 | 0.4.10-26.el8jbcs | RHSA-2022:1389 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 8 | libxml2-devel | 2.9.7-9.el8_4.2 | ALSA-2021:2569 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 8 | libxml2 | 2.9.7-9.el8_4.2 | RLSA-2021:2569 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP3 | libxml2 +1 | 2.9.7-3.37.1 | SUSE-SU-2023:2048-1, SUSE-SU-2021:1917-1 |
| SLES 15 SP2 | libxml2 +1 | 2.9.7-3.37.1 | SUSE-SU-2023:2048-1, SUSE-SU-2021:1917-1 |
| SLES 15 SP1 | libxml2 +1 | 2.9.7-150000.3.57.1 | SUSE-SU-2023:2048-1 |
| SLES 12 SP5 | libxml2 +1 | 2.9.4-46.46.1 | SUSE-SU-2021:2016-1 |
| SLES 2 | python-libxml2-python | 2.9.7-3.37.1 | SUSE-SU-2021:1917-1 |
Show 15 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 SP3 | libxml2 +1 | 2.9.7-150000.3.57.1 | SUSE-SU-2023:2048-1 |
| SLES for SAP 15 SP2 | libxml2 +1 | 2.9.7-150000.3.57.1 | SUSE-SU-2023:2048-1 |
| SLES for SAP 15 SP1 | libxml2 +1 | 2.9.7-150000.3.57.1 | SUSE-SU-2023:2048-1 |
| SLES for SAP 12 SP5 | libxml2 +1 | 2.9.4-46.46.1 | SUSE-SU-2021:2016-1 |
| SLE Real Time 15 SP3 | libxml2 +1 | 2.9.7-150000.3.57.1 | SUSE-SU-2023:2048-1 |
| SLE Micro 5.2 | libxml2 +1 | 2.9.7-150000.3.57.1 | SUSE-SU-2023:2048-1 |
| SLE Micro 5.1 | libxml2 | 2.9.7-150000.3.57.1 | SUSE-SU-2023:2048-1 |
| SLE Micro 5.0 | libxml2 | 2.9.7-3.37.1 | SUSE-SU-2021:1917-1 |
| SLE HPC 15 SP3 | libxml2 +1 | 2.9.7-150000.3.57.1 | SUSE-SU-2023:2048-1 |
| SLE HPC 15 SP2 | libxml2 +1 | 2.9.7-150000.3.57.1 | SUSE-SU-2023:2048-1 |
| SLE HPC 15 SP1 | libxml2 +1 | 2.9.7-150000.3.57.1 | SUSE-SU-2023:2048-1 |
| SUSE Manager Server 4.2 | libxml2 +1 | 2.9.7-150000.3.57.1 | SUSE-SU-2023:2048-1 |
| SUSE Manager Proxy 4.2 | libxml2 +1 | 2.9.7-150000.3.57.1 | SUSE-SU-2023:2048-1 |
| SUSE Enterprise Storage 7.1 | libxml2 +1 | 2.9.7-150000.3.57.1 | SUSE-SU-2023:2048-1 |
| SUSE Enterprise Storage 7 | libxml2 +1 | 2.9.7-150000.3.57.1 | SUSE-SU-2023:2048-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | libxml2 | 2.9.12-1.2 | openSUSE-SU-2024:11016-1 |
| openSUSE Tumbleweed | ruby3.2-rubygem-nokogiri | 1.13.9-1.7 | openSUSE-SU-2024:13165-1 |
| openSUSE Tumbleweed | rubygem-nokogiri | 1.13.3-1.1 | openSUSE-SU-2026:10356-1, openSUSE-SU-2025:14697-1, openSUSE-SU-2024:14174-1 |
| openSUSE Leap 15.4 | python-libxml2-python | 2.9.7-150000.3.57.1 | SUSE-SU-2023:2048-1 |
| openSUSE Leap 15.3 | libxml2 +1 | 2.9.7-3.37.1 | openSUSE-SU-2021:1917-1 |
| openSUSE Leap 15.2 | libxml2 +1 | 2.9.7-lp152.10.15.1 | openSUSE-SU-2021:0886-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | libxml2 | 2.9.11-r0 | — |
| Alpine v3.23 | libxml2 | 2.9.11-r0 | — |
| Alpine v3.23 | qt5-qtwebengine | 5.15.3_git20211112-r0 | — |
| Alpine v3.22 | libxml2 | 2.9.11-r0 | — |
| Alpine v3.22 | qt5-qtwebengine | 5.15.3_git20211112-r0 | — |
| Alpine v3.21 | libxml2 | 2.9.11-r0 | — |
| Alpine v3.21 | qt5-qtwebengine | 5.15.3_git20211112-r0 | — |
| Alpine v3.20 | libxml2 | 2.9.11-r0 | — |
| Alpine v3.20 | qt5-qtwebengine | 5.15.3_git20211112-r0 | — |
Show 9 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | libxml2 | 2.9.11-r0 | — |
| Alpine v3.19 | qt5-qtwebengine | 5.15.3_git20211112-r0 | — |
| Alpine v3.18 | libxml2 | 2.9.11-r0 | — |
| Alpine v3.18 | qt5-qtwebengine | 5.15.3_git20211112-r0 | — |
| Alpine v3.17 | libxml2 | 2.9.11-r0 | — |
| Alpine v3.17 | qt5-qtwebengine | 5.15.3_git20211112-r0 | — |
| Alpine v3.16 | libxml2 | 2.9.11-r0 | — |
| Alpine v3.16 | qt5-qtwebengine | 5.15.3_git20211112-r0 | — |
| Alpine v3.15 | libxml2 | 2.9.11-r0 | — |
| Alpine v3.15 | qt5-qtwebengine | 5.15.3_git20211112-r0 | — |
| Alpine v3.14 | qt5-qtwebengine | 5.15.3_git20211112-r0 | — |
| Alpine v3.13 | libxml2 | 2.9.11-r0 | — |
| Alpine v3.12 | libxml2 | 2.9.12-r0 | — |
| Alpine v3.11 | libxml2 | 2.9.12-r0 | — |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2 | libxml2 +3 | 2.9.1-6.amzn2.5.3 | ALAS2-2021-1662 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 8 | libxml2 +2 | 2.9.7-9.0.1.el8_4.2 | ELSA-2021-2569 |
Advisories 25
- ALSA-2021:2569 Moderate: libxml2 security update AlmaLinux Security Advisories · Oct 29, 2026
- RHSA-2022:1389 Red Hat Security Advisory: Red Hat JBoss Core Services Apache HTTP Server 2.4.37 SP11 security update Red Hat Security Advisories (RHSA) · Oct 15, 2026
- RHSA-2021:2569 Red Hat Security Advisory: libxml2 security update Red Hat Security Advisories (RHSA) · Oct 15, 2026
- SSA-398330 SSA-398330: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP >= V3.1.0 and < V3.1.5 Siemens ProductCERT · Oct 13, 2026
- WID-SEC-2025-0227 IBM QRadar SIEM: Mehrere Schwachstellen BSI CERT-Bund (WID) · Aug 11, 2026
- USN-4991-1 libxml2 vulnerabilities Ubuntu Security Notices (USN) · Jun 29, 2026
- openSUSE-SU-2026:10356-1 ruby4.0-rubygem-nokogiri-1.18.9-1.4 on GA media SUSE / openSUSE Security Updates · Mar 14, 2026
- DLA-2669-1 libxml2 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- RLSA-2021:2569 Moderate: libxml2 security update Rocky Linux Security Advisories · Feb 4, 2026
- SUSE-SU-2023:2048-1 Security update for libxml2 SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2021:1917-1 Security update for libxml2 SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2021:2016-1 Security update for libxml2 SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2025:14697-1 ruby3.4-rubygem-nokogiri-1.18.2-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2021:1917-1 Security update for libxml2 SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:11016-1 libxml2-2-2.9.12-1.2 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2021:0886-1 Security update for libxml2 SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:13165-1 ruby3.2-rubygem-nokogiri-1.13.9-1.7 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:14174-1 ruby3.3-rubygem-nokogiri-1.15.5-1.5 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:11912-1 ruby3.1-rubygem-nokogiri-1.13.3-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- ICSA-23-348-10 Siemens SIMATIC S7-1500 CISA ICS & IT advisories · Aug 12, 2025
- WID-SEC-2022-1051 libxml2: Schwachstelle ermöglicht Denial of Service BSI CERT-Bund (WID) · Jun 30, 2025
- WID-SEC-2023-1614 Tenable Security Nessus Network Monitor: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 25, 2023
- ICSA-21-336-06 Hitachi Energy APM Edge CISA ICS & IT advisories · Dec 2, 2021
- ELSA-2021-2569 Moderate: libxml2 security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Jul 3, 2021
- ALAS2-2021-1662 Moderate: libxml2 security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Jun 22, 2021