CVE-2021-3516

26

FAUCET Score

CVE-2021-3516 is a use-after-free vulnerability in libxml2's xmllint, affecting versions prior to 2.9.11, including products from Debian, Fedora, NetApp, Oracle, Red Hat, and xmlsoft. This flaw carries a CVSS score of 7.8 (High), indicating that an unauthenticated attacker could achieve high impact to confidentiality, integrity, and availability by tricking a user into processing a specially crafted file. There is no evidence of active exploitation, public exploit code (Metasploit, Nuclei, ExploitDB), or significant community discussion surrounding this vulnerability.

Impacted Technologies

Vendor	Product	Version(s)	CPE
		< 2.9.11CPE matchmatch criteria	cpe:2.3:a:xmlsoft:xmllint::::::::
		9.0CPE matchmatch criteria	cpe:2.3:o:debian:debian_linux:9.0:::::::*
		33CPE matchmatch criteria	cpe:2.3:o:fedoraproject:fedora:33:::::::*
		34CPE matchmatch criteria	cpe:2.3:o:fedoraproject:fedora:34:::::::*
		Range not provided by sourceCPE matchmatch criteria	cpe:2.3:a:redhat:jboss_core_services:-:::::::*

CVSS Data

CVSS version used by this source: 3.1

7.8HIGH

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Attack Vector

LOCAL

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

REQUIRED

Scope

UNCHANGED

Confidentiality Impact

HIGH

Integrity Impact

HIGH

Availability Impact

HIGH

Exploitability Score

1.8

Impact Score

5.9

CvssVersion

3.1

Exploit Intelligence

EPSS Score

1.99%

Probability of exploitation in next 30 days

EPSS Percentile

78.5%

Percentile rank of EPSS score among Peer Group

As of 2026-07-27

Model: v2026.06.15

This CVE's current EPSS score of 0.0199 is in the 77th percentile among its peer group of 11,617 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.1 Reddit, 0.1 Bluesky, 0.0 Mastodon, and 0.2 GitHub mentions.

Media Mentions

The average CVE in this peer group has 0.3 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Patch Available

Vendor Patches (40)

oraclepatch availablevia nvd_reference

redhatpatch availablevia redhat_api

Product: JBoss Core Services for RHEL 8Fixed in: jbcs-httpd24-openssl-1:1.1.1g-11.el8jbcs

redhatpatch availablevia redhat_api

Product: JBoss Core Services for RHEL 8Fixed in: jbcs-httpd24-apr-util-0:1.6.1-91.el8jbcs

redhatpatch availablevia redhat_api

Product: JBoss Core Services for RHEL 8Fixed in: jbcs-httpd24-curl-0:7.78.0-3.el8jbcs

redhatpatch availablevia redhat_api

Product: JBoss Core Services for RHEL 8Fixed in: jbcs-httpd24-httpd-0:2.4.37-80.el8jbcs

redhatpatch availablevia redhat_api

Product: JBoss Core Services for RHEL 8Fixed in: jbcs-httpd24-mod_cluster-native-0:1.3.16-10.Final_redhat_2.el8jbcs

redhatpatch availablevia redhat_api

Product: JBoss Core Services for RHEL 8Fixed in: jbcs-httpd24-mod_http2-0:1.15.7-22.el8jbcs

redhatpatch availablevia redhat_api

Product: JBoss Core Services for RHEL 8Fixed in: jbcs-httpd24-mod_jk-0:1.2.48-29.redhat_1.el8jbcs

redhatpatch availablevia redhat_api

Product: JBoss Core Services for RHEL 8Fixed in: jbcs-httpd24-mod_md-1:2.0.8-41.el8jbcs

redhatpatch availablevia redhat_api

Product: JBoss Core Services for RHEL 8Fixed in: jbcs-httpd24-mod_security-0:2.9.2-68.GA.el8jbcs

redhatpatch availablevia redhat_api

Product: JBoss Core Services for RHEL 8Fixed in: jbcs-httpd24-nghttp2-0:1.39.2-41.el8jbcs

redhatpatch availablevia redhat_api

Product: JBoss Core Services for RHEL 8Fixed in: jbcs-httpd24-openssl-chil-0:1.0.0-11.el8jbcs

redhatpatch availablevia redhat_api

Product: JBoss Core Services for RHEL 8Fixed in: jbcs-httpd24-openssl-pkcs11-0:0.4.10-26.el8jbcs

redhatpatch availablevia redhat_api

Product: JBoss Core Services on RHEL 7Fixed in: jbcs-httpd24-apr-util-0:1.6.1-91.jbcs.el7

redhatpatch availablevia redhat_api

Product: JBoss Core Services on RHEL 7Fixed in: jbcs-httpd24-curl-0:7.78.0-3.jbcs.el7

redhatpatch availablevia redhat_api

Product: JBoss Core Services on RHEL 7Fixed in: jbcs-httpd24-httpd-0:2.4.37-80.jbcs.el7

redhatpatch availablevia redhat_api

Product: JBoss Core Services on RHEL 7Fixed in: jbcs-httpd24-mod_cluster-native-0:1.3.16-10.Final_redhat_2.jbcs.el7

redhatpatch availablevia redhat_api

Product: JBoss Core Services on RHEL 7Fixed in: jbcs-httpd24-mod_http2-0:1.15.7-22.jbcs.el7

redhatpatch availablevia redhat_api

Product: JBoss Core Services on RHEL 7Fixed in: jbcs-httpd24-mod_jk-0:1.2.48-29.redhat_1.jbcs.el7

redhatpatch availablevia redhat_api

Product: JBoss Core Services on RHEL 7Fixed in: jbcs-httpd24-mod_md-1:2.0.8-41.jbcs.el7

redhatpatch availablevia redhat_api

Product: JBoss Core Services on RHEL 7Fixed in: jbcs-httpd24-mod_security-0:2.9.2-68.GA.jbcs.el7

redhatpatch availablevia redhat_api

Product: JBoss Core Services on RHEL 7Fixed in: jbcs-httpd24-nghttp2-0:1.39.2-41.jbcs.el7

redhatpatch availablevia redhat_api

Product: JBoss Core Services on RHEL 7Fixed in: jbcs-httpd24-openssl-1:1.1.1g-11.jbcs.el7

redhatpatch availablevia redhat_api

Product: JBoss Core Services on RHEL 7Fixed in: jbcs-httpd24-openssl-chil-0:1.0.0-11.jbcs.el7

redhatpatch availablevia redhat_api

Product: JBoss Core Services on RHEL 7Fixed in: jbcs-httpd24-openssl-pkcs11-0:0.4.10-26.jbcs.el7

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 8Fixed in: libxml2-0:2.9.7-9.el8_4.2

redhatpatch availablevia redhat_api

Product: Red Hat Migration Toolkit for Containers 1.4Fixed in: rhmtc/openshift-migration-controller-rhel8:v1.4.6-4

redhatpatch availablevia redhat_api

Product: Red Hat Migration Toolkit for Containers 1.4Fixed in: rhmtc/openshift-migration-log-reader-rhel8:v1.4.6-4

redhatpatch availablevia redhat_api

Product: Red Hat Migration Toolkit for Containers 1.4Fixed in: rhmtc/openshift-migration-must-gather-rhel8:v1.4.6-4

redhatpatch availablevia redhat_api

Product: Red Hat Migration Toolkit for Containers 1.4Fixed in: rhmtc/openshift-migration-operator-bundle:v1.4.6-5

redhatpatch availablevia redhat_api

Product: Red Hat Migration Toolkit for Containers 1.4Fixed in: rhmtc/openshift-migration-registry-rhel8:v1.4.6-4

redhatpatch availablevia redhat_api

Product: Red Hat Migration Toolkit for Containers 1.4Fixed in: rhmtc/openshift-migration-rsync-transfer-rhel8:v1.4.6-4

redhatpatch availablevia redhat_api

Product: Red Hat Migration Toolkit for Containers 1.4Fixed in: rhmtc/openshift-migration-ui-rhel8:v1.4.6-4

redhatpatch availablevia redhat_api

Product: Red Hat Migration Toolkit for Containers 1.4Fixed in: rhmtc/openshift-migration-velero-plugin-for-aws-rhel8:v1.4.6-4

redhatpatch availablevia redhat_api

Product: Red Hat Migration Toolkit for Containers 1.4Fixed in: rhmtc/openshift-migration-velero-plugin-for-gcp-rhel8:v1.4.6-3

redhatpatch availablevia redhat_api

Product: Red Hat Migration Toolkit for Containers 1.4Fixed in: rhmtc/openshift-migration-velero-plugin-for-microsoft-azure-rhel8:v1.4.6-4

redhatpatch availablevia redhat_api

Product: Red Hat Migration Toolkit for Containers 1.4Fixed in: rhmtc/openshift-migration-velero-restic-restore-helper-rhel8:v1.4.6-5

redhatpatch availablevia redhat_api

Product: Red Hat Migration Toolkit for Containers 1.4Fixed in: rhmtc/openshift-migration-velero-rhel8:v1.4.6-5

redhatpatch availablevia redhat_api

Product: Red Hat Migration Toolkit for Containers 1.4Fixed in: rhmtc/openshift-velero-plugin-rhel8:v1.4.6-4

redhatpatch availablevia redhat_api

Product: Text-Only JBCSFixed in: libxml2

Vendor Advisories (1)

redhatCVE-2021-3516Moderate

libxml2: Use-after-free in xmlEncodeEntitiesInternal() in entities.c

References

bugzilla.redhat.com / show_bug.cgi

Issue TrackingThird Party Advisory

gitlab.gnome.org / GNOME/libxml2/-/commit/1358d157d0bd83be1dfe356a69213df9fac0b539

PatchThird Party Advisory

gitlab.gnome.org / GNOME/libxml2/-/issues/230

ExploitIssue TrackingThird Party Advisory

lists.debian.org / debian-lts-announce/2021/05/msg00008.html

Mailing ListThird Party Advisory

lists.fedoraproject.org / archives/list/package-announce%40lists.fedoraproject.org/message/BZOMV5J4PMZAORVT64BKLV6YIZAFDGX6

lists.fedoraproject.org / archives/list/package-announce%40lists.fedoraproject.org/message/QVM4UJ3376I6ZVOYMHBNX4GY3NIV52WV

security.gentoo.org / glsa/202107-05

Third Party Advisory

security.netapp.com / advisory/ntap-20210716-0005

Third Party Advisory

oracle.com / security-alerts/cpujan2022.html

PatchThird Party Advisory