libxml2: Use-after-free in xmlEncodeEntitiesInternal() in entities.c
Published Jun 1, 2021
7.8
HIGHCVSS 3.1
EPSS 1.99%
Description
There's a flaw in libxml2's xmllint in versions before 2.9.11. An attacker who is able to submit a crafted file to be processed by xmllint could trigger a use-after-free. The greatest impact of this flaw is to confidentiality, integrity, and availability.
Affected products
- Vendor n/a Product Libxml2 Defaultn/a
- Version libxml2 2.9.11StatusaffectedConstraints-
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
|---|---|---|---|---|---|---|---|---|---|
| n/a | Libxml2 | n/a |
|
Configuration 2
- 9.0
Configuration 3
- 33
- 34
Configuration 4
- n/a
- 6.0
- 7.0
- 8.0
Configuration 5
- n/a
- n/a
- n/a
Configuration 6
- 8.8
No data.
JBoss Core Services for RHEL 8
jbcs-httpd24-apr-util-0:1.6.1-91.el8jbcs
Fixed · RHSA-2022:1389
JBoss Core Services for RHEL 8
jbcs-httpd24-curl-0:7.78.0-3.el8jbcs
Fixed · RHSA-2022:1389
JBoss Core Services for RHEL 8
jbcs-httpd24-httpd-0:2.4.37-80.el8jbcs
Fixed · RHSA-2022:1389
JBoss Core Services for RHEL 8
jbcs-httpd24-mod_cluster-native-0:1.3.16-10.Final_redhat_2.el8jbcs
Fixed · RHSA-2022:1389
JBoss Core Services for RHEL 8
jbcs-httpd24-mod_http2-0:1.15.7-22.el8jbcs
Fixed · RHSA-2022:1389
JBoss Core Services for RHEL 8
jbcs-httpd24-mod_jk-0:1.2.48-29.redhat_1.el8jbcs
Fixed · RHSA-2022:1389
JBoss Core Services for RHEL 8
jbcs-httpd24-mod_md-1:2.0.8-41.el8jbcs
Fixed · RHSA-2022:1389
JBoss Core Services for RHEL 8
jbcs-httpd24-mod_security-0:2.9.2-68.GA.el8jbcs
Fixed · RHSA-2022:1389
JBoss Core Services for RHEL 8
jbcs-httpd24-nghttp2-0:1.39.2-41.el8jbcs
Fixed · RHSA-2022:1389
JBoss Core Services for RHEL 8
jbcs-httpd24-openssl-1:1.1.1g-11.el8jbcs
Fixed · RHSA-2022:1389
JBoss Core Services for RHEL 8
jbcs-httpd24-openssl-chil-0:1.0.0-11.el8jbcs
Fixed · RHSA-2022:1389
JBoss Core Services for RHEL 8
jbcs-httpd24-openssl-pkcs11-0:0.4.10-26.el8jbcs
Fixed · RHSA-2022:1389
JBoss Core Services on RHEL 7
jbcs-httpd24-apr-util-0:1.6.1-91.jbcs.el7
Fixed · RHSA-2022:1389
JBoss Core Services on RHEL 7
jbcs-httpd24-curl-0:7.78.0-3.jbcs.el7
Fixed · RHSA-2022:1389
JBoss Core Services on RHEL 7
jbcs-httpd24-httpd-0:2.4.37-80.jbcs.el7
Fixed · RHSA-2022:1389
JBoss Core Services on RHEL 7
jbcs-httpd24-mod_cluster-native-0:1.3.16-10.Final_redhat_2.jbcs.el7
Fixed · RHSA-2022:1389
JBoss Core Services on RHEL 7
jbcs-httpd24-mod_http2-0:1.15.7-22.jbcs.el7
Fixed · RHSA-2022:1389
JBoss Core Services on RHEL 7
jbcs-httpd24-mod_jk-0:1.2.48-29.redhat_1.jbcs.el7
Fixed · RHSA-2022:1389
JBoss Core Services on RHEL 7
jbcs-httpd24-mod_md-1:2.0.8-41.jbcs.el7
Fixed · RHSA-2022:1389
JBoss Core Services on RHEL 7
jbcs-httpd24-mod_security-0:2.9.2-68.GA.jbcs.el7
Fixed · RHSA-2022:1389
JBoss Core Services on RHEL 7
jbcs-httpd24-nghttp2-0:1.39.2-41.jbcs.el7
Fixed · RHSA-2022:1389
JBoss Core Services on RHEL 7
jbcs-httpd24-openssl-1:1.1.1g-11.jbcs.el7
Fixed · RHSA-2022:1389
JBoss Core Services on RHEL 7
jbcs-httpd24-openssl-chil-0:1.0.0-11.jbcs.el7
Fixed · RHSA-2022:1389
JBoss Core Services on RHEL 7
jbcs-httpd24-openssl-pkcs11-0:0.4.10-26.jbcs.el7
Fixed · RHSA-2022:1389
Red Hat Enterprise Linux 8
libxml2-0:2.9.7-9.el8_4.2
Fixed · RHSA-2021:2569
Red Hat Enterprise Linux 8
libxml2-0:2.9.7-9.el8_4.2
Fixed · RHSA-2021:2569
Red Hat Migration Toolkit for Containers 1.4
rhmtc/openshift-migration-controller-rhel8:v1.4.6-4
Fixed · RHBA-2021:2854
Red Hat Migration Toolkit for Containers 1.4
rhmtc/openshift-migration-log-reader-rhel8:v1.4.6-4
Fixed · RHBA-2021:2854
Red Hat Migration Toolkit for Containers 1.4
rhmtc/openshift-migration-must-gather-rhel8:v1.4.6-4
Fixed · RHBA-2021:2854
Red Hat Migration Toolkit for Containers 1.4
rhmtc/openshift-migration-operator-bundle:v1.4.6-5
Fixed · RHBA-2021:2854
Red Hat Migration Toolkit for Containers 1.4
rhmtc/openshift-migration-registry-rhel8:v1.4.6-4
Fixed · RHBA-2021:2854
Red Hat Migration Toolkit for Containers 1.4
rhmtc/openshift-migration-rsync-transfer-rhel8:v1.4.6-4
Fixed · RHBA-2021:2854
Red Hat Migration Toolkit for Containers 1.4
rhmtc/openshift-migration-ui-rhel8:v1.4.6-4
Fixed · RHBA-2021:2854
Red Hat Migration Toolkit for Containers 1.4
rhmtc/openshift-migration-velero-plugin-for-aws-rhel8:v1.4.6-4
Fixed · RHBA-2021:2854
Red Hat Migration Toolkit for Containers 1.4
rhmtc/openshift-migration-velero-plugin-for-gcp-rhel8:v1.4.6-3
Fixed · RHBA-2021:2854
Red Hat Migration Toolkit for Containers 1.4
rhmtc/openshift-migration-velero-plugin-for-microsoft-azure-rhel8:v1.4.6-4
Fixed · RHBA-2021:2854
Red Hat Migration Toolkit for Containers 1.4
rhmtc/openshift-migration-velero-restic-restore-helper-rhel8:v1.4.6-5
Fixed · RHBA-2021:2854
Red Hat Migration Toolkit for Containers 1.4
rhmtc/openshift-migration-velero-rhel8:v1.4.6-5
Fixed · RHBA-2021:2854
Red Hat Migration Toolkit for Containers 1.4
rhmtc/openshift-velero-plugin-rhel8:v1.4.6-4
Fixed · RHBA-2021:2854
Red Hat Enterprise Linux 6
compat-expat1
Out of support scope
Red Hat Enterprise Linux 6
libxml2
Out of support scope
Red Hat Enterprise Linux 7
libxml2
Out of support scope
Red Hat Enterprise Linux 9
libxml2
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| JBoss Core Services for RHEL 8 | jbcs-httpd24-apr-util-0:1.6.1-91.el8jbcs | Fixed | RHSA-2022:1389 |
| JBoss Core Services for RHEL 8 | jbcs-httpd24-curl-0:7.78.0-3.el8jbcs | Fixed | RHSA-2022:1389 |
| JBoss Core Services for RHEL 8 | jbcs-httpd24-httpd-0:2.4.37-80.el8jbcs | Fixed | RHSA-2022:1389 |
| JBoss Core Services for RHEL 8 | jbcs-httpd24-mod_cluster-native-0:1.3.16-10.Final_redhat_2.el8jbcs | Fixed | RHSA-2022:1389 |
| JBoss Core Services for RHEL 8 | jbcs-httpd24-mod_http2-0:1.15.7-22.el8jbcs | Fixed | RHSA-2022:1389 |
| JBoss Core Services for RHEL 8 | jbcs-httpd24-mod_jk-0:1.2.48-29.redhat_1.el8jbcs | Fixed | RHSA-2022:1389 |
| JBoss Core Services for RHEL 8 | jbcs-httpd24-mod_md-1:2.0.8-41.el8jbcs | Fixed | RHSA-2022:1389 |
| JBoss Core Services for RHEL 8 | jbcs-httpd24-mod_security-0:2.9.2-68.GA.el8jbcs | Fixed | RHSA-2022:1389 |
| JBoss Core Services for RHEL 8 | jbcs-httpd24-nghttp2-0:1.39.2-41.el8jbcs | Fixed | RHSA-2022:1389 |
| JBoss Core Services for RHEL 8 | jbcs-httpd24-openssl-1:1.1.1g-11.el8jbcs | Fixed | RHSA-2022:1389 |
| JBoss Core Services for RHEL 8 | jbcs-httpd24-openssl-chil-0:1.0.0-11.el8jbcs | Fixed | RHSA-2022:1389 |
| JBoss Core Services for RHEL 8 | jbcs-httpd24-openssl-pkcs11-0:0.4.10-26.el8jbcs | Fixed | RHSA-2022:1389 |
| JBoss Core Services on RHEL 7 | jbcs-httpd24-apr-util-0:1.6.1-91.jbcs.el7 | Fixed | RHSA-2022:1389 |
| JBoss Core Services on RHEL 7 | jbcs-httpd24-curl-0:7.78.0-3.jbcs.el7 | Fixed | RHSA-2022:1389 |
| JBoss Core Services on RHEL 7 | jbcs-httpd24-httpd-0:2.4.37-80.jbcs.el7 | Fixed | RHSA-2022:1389 |
| JBoss Core Services on RHEL 7 | jbcs-httpd24-mod_cluster-native-0:1.3.16-10.Final_redhat_2.jbcs.el7 | Fixed | RHSA-2022:1389 |
| JBoss Core Services on RHEL 7 | jbcs-httpd24-mod_http2-0:1.15.7-22.jbcs.el7 | Fixed | RHSA-2022:1389 |
| JBoss Core Services on RHEL 7 | jbcs-httpd24-mod_jk-0:1.2.48-29.redhat_1.jbcs.el7 | Fixed | RHSA-2022:1389 |
| JBoss Core Services on RHEL 7 | jbcs-httpd24-mod_md-1:2.0.8-41.jbcs.el7 | Fixed | RHSA-2022:1389 |
| JBoss Core Services on RHEL 7 | jbcs-httpd24-mod_security-0:2.9.2-68.GA.jbcs.el7 | Fixed | RHSA-2022:1389 |
| JBoss Core Services on RHEL 7 | jbcs-httpd24-nghttp2-0:1.39.2-41.jbcs.el7 | Fixed | RHSA-2022:1389 |
| JBoss Core Services on RHEL 7 | jbcs-httpd24-openssl-1:1.1.1g-11.jbcs.el7 | Fixed | RHSA-2022:1389 |
| JBoss Core Services on RHEL 7 | jbcs-httpd24-openssl-chil-0:1.0.0-11.jbcs.el7 | Fixed | RHSA-2022:1389 |
| JBoss Core Services on RHEL 7 | jbcs-httpd24-openssl-pkcs11-0:0.4.10-26.jbcs.el7 | Fixed | RHSA-2022:1389 |
| Red Hat Enterprise Linux 8 | libxml2-0:2.9.7-9.el8_4.2 | Fixed | RHSA-2021:2569 |
| Red Hat Enterprise Linux 8 | libxml2-0:2.9.7-9.el8_4.2 | Fixed | RHSA-2021:2569 |
| Red Hat Migration Toolkit for Containers 1.4 | rhmtc/openshift-migration-controller-rhel8:v1.4.6-4 | Fixed | RHBA-2021:2854 |
| Red Hat Migration Toolkit for Containers 1.4 | rhmtc/openshift-migration-log-reader-rhel8:v1.4.6-4 | Fixed | RHBA-2021:2854 |
| Red Hat Migration Toolkit for Containers 1.4 | rhmtc/openshift-migration-must-gather-rhel8:v1.4.6-4 | Fixed | RHBA-2021:2854 |
| Red Hat Migration Toolkit for Containers 1.4 | rhmtc/openshift-migration-operator-bundle:v1.4.6-5 | Fixed | RHBA-2021:2854 |
| Red Hat Migration Toolkit for Containers 1.4 | rhmtc/openshift-migration-registry-rhel8:v1.4.6-4 | Fixed | RHBA-2021:2854 |
| Red Hat Migration Toolkit for Containers 1.4 | rhmtc/openshift-migration-rsync-transfer-rhel8:v1.4.6-4 | Fixed | RHBA-2021:2854 |
| Red Hat Migration Toolkit for Containers 1.4 | rhmtc/openshift-migration-ui-rhel8:v1.4.6-4 | Fixed | RHBA-2021:2854 |
| Red Hat Migration Toolkit for Containers 1.4 | rhmtc/openshift-migration-velero-plugin-for-aws-rhel8:v1.4.6-4 | Fixed | RHBA-2021:2854 |
| Red Hat Migration Toolkit for Containers 1.4 | rhmtc/openshift-migration-velero-plugin-for-gcp-rhel8:v1.4.6-3 | Fixed | RHBA-2021:2854 |
| Red Hat Migration Toolkit for Containers 1.4 | rhmtc/openshift-migration-velero-plugin-for-microsoft-azure-rhel8:v1.4.6-4 | Fixed | RHBA-2021:2854 |
| Red Hat Migration Toolkit for Containers 1.4 | rhmtc/openshift-migration-velero-restic-restore-helper-rhel8:v1.4.6-5 | Fixed | RHBA-2021:2854 |
| Red Hat Migration Toolkit for Containers 1.4 | rhmtc/openshift-migration-velero-rhel8:v1.4.6-5 | Fixed | RHBA-2021:2854 |
| Red Hat Migration Toolkit for Containers 1.4 | rhmtc/openshift-velero-plugin-rhel8:v1.4.6-4 | Fixed | RHBA-2021:2854 |
| Red Hat Enterprise Linux 6 | compat-expat1 | Out of support scope | n/a |
| Red Hat Enterprise Linux 6 | libxml2 | Out of support scope | n/a |
| Red Hat Enterprise Linux 7 | libxml2 | Out of support scope | n/a |
| Red Hat Enterprise Linux 9 | libxml2 | Not affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
The only known exploitation path of this flaw is via the xmllint tool. This flaw is out of support scope for Red Hat Enterprise Linux 6 and 7. To learn more about Red Hat Enterprise Linux support life cycles, please see https://access.redhat.com/support/policy/updates/errata .
Red Hat mitigation
This flaw can be mitigated by not using xmllint with the --html and --push options together.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
No CVSS v3.0 score for this CVE.
AV:N/AC:M/Au:N/C:P/I:P/A:P
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2021–2026- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
- EPSS v4
Percentile over time
- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
- EPSS v4
Table of values (23 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 1.99% (0.01990) | 79.89th | v5 (v2026.06.15) |
| Jun 15, 2026 | 1.99% (0.01990) | 77.97th | v5 (v2026.06.15) |
| Mar 30, 2025 | 0.35% (0.00354) | 54.79th | v4 (v2025.03.14) |
| Mar 29, 2025 | 4.46% (0.04461) | 81.42th | v4 (v2025.03.14) |
| Mar 28, 2025 | 0.35% (0.00354) | 54.81th | v4 (v2025.03.14) |
| Mar 27, 2025 | 4.46% (0.04461) | 87.59th | v4 (v2025.03.14) |
| Mar 20, 2025 | 0.35% (0.00354) | 55.02th | v4 (v2025.03.14) |
| Mar 19, 2025 | 4.46% (0.04461) | 87.73th | v4 (v2025.03.14) |
| Mar 17, 2025 | 0.35% (0.00354) | 55.57th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.15% (0.00151) | 52.70th | v3 (v2023.03.01) |
| Feb 15, 2024 | 0.15% (0.00151) | 50.10th | v3 (v2023.03.01) |
| Jan 6, 2024 | 0.13% (0.00132) | 48.04th | v3 (v2023.03.01) |
| Nov 8, 2023 | 0.13% (0.00126) | 46.98th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.09% (0.00089) | 36.24th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.54% (0.01537) | 74.52th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.54% (0.01537) | 72.41th | v2 (v2022.01.01) |
| Mar 31, 2022 | 5.13% (0.05132) | 75.66th | v2 (v2022.01.01) |
| Feb 4, 2022 | 4.71% (0.04713) | 74.50th | v2 (v2022.01.01) |
| Feb 3, 2022 | 7.85% (0.07855) | 85.01th | v1 |
| Jan 6, 2022 | 7.85% (0.07855) | 84.84th | v1 |
| Jan 5, 2022 | 1.86% (0.01865) | 76.93th | v5 (v2026.06.15) |
| Jun 8, 2021 | 1.25% (0.01247) | 0.00th | v1 |
| Jun 2, 2021 | 0.42% (0.00416) | 0.00th | v1 |
References (12)
- https://access.redhat.com/security/cve/CVE-2021-3516 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1954225 x_refsource_MISCIssue TrackingThird Party Advisory
- https://gitlab.gnome.org/GNOME/libxml2/-/commit/1358d157d0bd83be1dfe356a69213df9fac0b539 x_refsource_MISCPatchThird Party Advisory
- https://gitlab.gnome.org/GNOME/libxml2/-/issues/230 x_refsource_MISCExploitIssue TrackingThird Party Advisory
- https://lists.debian.org/debian-lts-announce/2021/05/msg00008.html mailing-listx_refsource_MLISTMailing ListThird Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BZOMV5J4PMZAORVT64BKLV6YIZAFDGX6/ vendor-advisoryx_refsource_FEDORA
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QVM4UJ3376I6ZVOYMHBNX4GY3NIV52WV/ vendor-advisoryx_refsource_FEDORA
- https://nvd.nist.gov/vuln/detail/CVE-2021-3516
- https://security.gentoo.org/glsa/202107-05 vendor-advisoryx_refsource_GENTOOThird Party Advisory
- https://security.netapp.com/advisory/ntap-20210716-0005/ x_refsource_CONFIRMThird Party Advisory
- https://www.cve.org/CVERecord?id=CVE-2021-3516
- https://www.oracle.com/security-alerts/cpujan2022.html x_refsource_MISCPatchThird Party Advisory
Change history (0)
No recorded changes yet.