CVE-2021-3517: Buffer Overflow

Published Apr 22, 2021
·
Updated

A heap-based buffer overflow was found in libxml2 when processing truncated UTF-8 input.

Reference: https://gitlab.gnome.org/GNOME/libxml2/-/issues/235

Upstream patch: https://gitlab.gnome.org/GNOME/libxml2/-/commit/bf22713507fe1fc3a2c4b525cf0a88c2dc87a3a2

Other sources

GNOME libxml2 is vulnerable to a heap-based buffer overflow, caused by improper bounds checking by xmlEncodeEntitiesInternal() in entities.c. By sending a specially crafted file, a remote attacker could trigger an out-of-bounds read and execute arbitrary code on the system or cause a denial of service.

IBM

There is a flaw in the xml entity encoding functionality of libxml2 in versions before 2.9.11. An attacker who is able to supply a crafted file to be processed by an application linked with the affected functionality of libxml2 could trigger an out-of-bounds read. The most likely impact of this flaw is to application availability, with some potential impact to confidentiality and integrity if an attacker is able to use memory information to further exploit the application.

There is a flaw in the xml entity encoding functionality of libxml2. An attacker who is able to supply a crafted file to be processed by an application linked with the affected functionality of libxml2 could trigger an out-of-bounds read. The most likely impact of this flaw is to application availability, with some potential impact to confidentiality and integrity if an attacker is able to use memory information to further exploit the application.

Affected Software

54 affected componentsFixes available
rubygems/nokogiri<1.11.4
1.11.4
redhat/jbcs-httpd24-apr-util<0:1.6.1-91.el8
0:1.6.1-91.el8
redhat/jbcs-httpd24-curl<0:7.78.0-3.el8
0:7.78.0-3.el8
redhat/jbcs-httpd24-httpd<0:2.4.37-80.el8
0:2.4.37-80.el8
redhat/jbcs-httpd24-nghttp2<0:1.39.2-41.el8
0:1.39.2-41.el8
redhat/jbcs-httpd24-openssl<1:1.1.1g-11.el8
1:1.1.1g-11.el8
redhat/jbcs-httpd24-openssl-chil<0:1.0.0-11.el8
0:1.0.0-11.el8
redhat/jbcs-httpd24-openssl-pkcs11<0:0.4.10-26.el8
0:0.4.10-26.el8
redhat/jbcs-httpd24-apr-util<0:1.6.1-91.jbcs.el7
0:1.6.1-91.jbcs.el7
redhat/jbcs-httpd24-curl<0:7.78.0-3.jbcs.el7
0:7.78.0-3.jbcs.el7
redhat/jbcs-httpd24-httpd<0:2.4.37-80.jbcs.el7
0:2.4.37-80.jbcs.el7
redhat/jbcs-httpd24-nghttp2<0:1.39.2-41.jbcs.el7
0:1.39.2-41.jbcs.el7
redhat/jbcs-httpd24-openssl<1:1.1.1g-11.jbcs.el7
1:1.1.1g-11.jbcs.el7
redhat/jbcs-httpd24-openssl-chil<0:1.0.0-11.jbcs.el7
0:1.0.0-11.jbcs.el7
redhat/jbcs-httpd24-openssl-pkcs11<0:0.4.10-26.jbcs.el7
0:0.4.10-26.jbcs.el7
redhat/libxml2<0:2.9.7-9.el8_4.2
0:2.9.7-9.el8_4.2
redhat/libxml2<2.9.11
2.9.11
IBM Security Verify Access<=10.0.0
Xmlsoft Libxml2<2.9.11
redhat JBoss Core Services
redhat Enterprise Linux=8.0
Fedoraproject Fedora=33
Fedoraproject Fedora=34
Debian Debian Linux=9.0
NetApp Active Iq Unified Manager Vmware Vsphere
NetApp Active Iq Unified Manager Windows
NetApp Clustered Data ONTAP
NetApp Clustered Data Ontap Antivirus Connector
NetApp E-Series SANtricity OS Controller>=11.0.0<=11.70.1
NetApp E-series Santricity Storage Manager
NetApp E-series Santricity Web Services Web Services Proxy
NetApp Hci Management Node
NetApp Manageability Software Development Kit
NetApp OnCommand Insight
NetApp OnCommand Workflow Automation
NetApp ONTAP Select Deploy administration utility
NetApp Santricity Unified Manager
NetApp Snapdrive Windows
NetApp Snapmanager Oracle
NetApp Snapmanager Sap
NetApp Solidfire
NetApp Hci H410c Firmware
NetApp Hci H410c
Oracle Communications Cloud Native Core Network Function Cloud Native Environment=1.10.0
Oracle Enterprise Manager Base Platform=13.4.0.0
Oracle Enterprise Manager Base Platform=13.5.0.0
Oracle MySQL Workbench<=8.0.26
Oracle OpenJDK=8-update301
Oracle PeopleSoft Enterprise PeopleTools=8.58
Oracle Real User Experience Insight=13.4.1.0
Oracle Real User Experience Insight=13.5.1.0
Oracle ZFS Storage Appliance Kit=8.8
All of the following
NetApp Hci H410c Firmware
NetApp Hci H410c

Event History

Apr 22, 2021
CVE Published
12:00 AM
Apr 27, 2021
Data Sourced
via Red Hat·06:54 PM
DescriptionSeverityAffected Software
May 19, 2021
CVE Published
via MITRE·01:45 PM
Data Sourced
via MITRE·01:45 PM
DescriptionWeakness
Data Sourced
via NVD·02:15 PM
RemedyDescriptionSeverityWeaknessAffected Software
May 24, 2022
Advisory Published
07:02 PM

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the vulnerability ID?

The vulnerability ID is CVE-2021-3517.

2

What is the severity of CVE-2021-3517?

The severity of CVE-2021-3517 is high with a CVSS score of 8.6.

3

What is the affected software?

The affected software includes libxml2 versions before 2.9.11, Nokogiri version up to 1.11.4, and certain Red Hat packages.

4

How does the vulnerability occur?

The vulnerability occurs due to a heap-based buffer overflow caused by improper bounds checking in the xml entity encoding functionality of libxml2.

5

Is there a fix available for CVE-2021-3517?

Yes, a fix is available. Update to libxml2 version 2.9.11 or higher, or follow the recommended remediation for the affected software packages.

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