CVE-2021-3518: Use After Free

Published Apr 22, 2021
·
Updated

ActionKit. An input validation issue was addressed with improved input validation.

Other sources

AMD Kernel. A memory corruption issue was addressed with improved input validation.

— Apple

An use-after-free was found in libxml2 in xmlXIncludeDoProcess() in xinclude.c when processing crafted files.

Reference: https://gitlab.gnome.org/GNOME/libxml2/-/issues/237

Upstream patch: https://gitlab.gnome.org/GNOME/libxml2/-/commit/1098c30a040e72a4654968547f415be4e4c40fe7

— Red Hat

Analytics. A logic issue was addressed with improved restrictions.

— Apple

Analytics. This issue was addressed with a new entitlement.

— Apple

App Store. A permissions issue was addressed with improved validation.

— Apple

Credit

CVE-2021-3518, George Nosenko, JunDong Xie(Ant Security Light), ryuzaki, Mickey Jin@@patch1t(Trend Micro), Sunglin(Knownsec 404 team), Yizhuo Wang(Group of Software Security In Progress), Tim Michaud@@TimGMichaud(Zoom Video Communications), Linus Henze (pinauten.de), Csaba Fitzl@@theevilbit(Offensive Security), tr3e(Trend Micro Zero Day Initiative), hjy79425575(Trend Micro Zero Day Initiative), Matthew Denton(Google Chrome Security), Jzhu(Baidu Security), Ye Zhang@@co0py_Cat(Baidu Security), CFF(Topsec Alpha Team), CVE-2018-25010, CVE-2018-25011, CVE-2018-25014, CVE-2020-36328, CVE-2020-36329, CVE-2020-36330, CVE-2020-36331, Anonymous(Trend Micro Zero Day Initiative), Christoph Guttandin(Media Codings), Sergei Glazunov(Google Project Zero), Ivan Fratric(Google Project Zero), vm_call, Nozhdar Abdulkhaleq Shukri, Zachary Keffaber@@QuickUpdate5, Denis Tokarev@@illusionofcha0s, tr3e, Mickey Jin@@patch1t(Trend Micro working with Trend Micro Zero Day Initiative), Georgi Valkov (httpstorm.com), Zhongcheng Li (CK01), Ron Waisberg@@epsilan, Gary Nield(ECSC Group plc), Wojciech Reguła@@_r3ggi(SecuRing), Matt Shockley (twitter.com/mattshockl)(Offensive Security), Liu Long(Ant Security Light), Yinyi Wu@@3ndy1(Qihoo 360 Vulcan Team), Zuozhi Fan@@pattern_F_(Ant Security TianQiong Lab), ABC Research s.r.o

Affected Software

47 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
Apple macOS Big Sur<11.5
11.5
Apple tvOS<14.7
14.7
Apple WatchOS<7.6
7.6
IBM Security Verify Access<=10.0.0
Xmlsoft Libxml2<2.9.11
Debian Debian Linux=9.0
redhat JBoss Core Services
redhat Enterprise Linux=8.0
Fedoraproject Fedora=33
Fedoraproject Fedora=34
NetApp Active Iq Unified Manager Vmware Vsphere
NetApp Clustered Data ONTAP
NetApp Clustered Data Ontap Antivirus Connector
NetApp Manageability Software Development Kit
NetApp ONTAP Select Deploy administration utility
NetApp Snapdrive Windows
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 Enterprise Manager Ops Center=12.4.0.0
Oracle MySQL Workbench<=8.0.26
Oracle PeopleSoft Enterprise PeopleTools=8.58
Oracle Real User Experience Insight=13.4.1.0
Oracle Real User Experience Insight=13.5.1.0
Apple iOS<14.7
14.7
Apple iPadOS<14.7
14.7
redhat/libxml2<2.9.11
2.9.11
All of the following
NetApp Hci H410c Firmware
NetApp Hci H410c

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade rubygems/nokogiri to a version that resolves this vulnerability.

    Fixed in 1.11.4
  2. Upgrade

    Upgrade redhat/jbcs-httpd24-apr-util to a version that resolves this vulnerability.

    Fixed in 0:1.6.1-91.el8
  3. Upgrade

    Upgrade redhat/jbcs-httpd24-curl to a version that resolves this vulnerability.

    Fixed in 0:7.78.0-3.el8
  4. Upgrade

    Upgrade redhat/jbcs-httpd24-httpd to a version that resolves this vulnerability.

    Fixed in 0:2.4.37-80.el8
  5. Upgrade

    Upgrade redhat/jbcs-httpd24-nghttp2 to a version that resolves this vulnerability.

    Fixed in 0:1.39.2-41.el8
  6. Upgrade

    Upgrade redhat/jbcs-httpd24-openssl to a version that resolves this vulnerability.

    Fixed in 1:1.1.1g-11.el8
  7. Upgrade

    Upgrade redhat/jbcs-httpd24-openssl-chil to a version that resolves this vulnerability.

    Fixed in 0:1.0.0-11.el8
  8. Upgrade

    Upgrade redhat/jbcs-httpd24-openssl-pkcs11 to a version that resolves this vulnerability.

    Fixed in 0:0.4.10-26.el8
  9. Upgrade

    Upgrade redhat/jbcs-httpd24-apr-util to a version that resolves this vulnerability.

    Fixed in 0:1.6.1-91.jbcs.el7
  10. Upgrade

    Upgrade redhat/jbcs-httpd24-curl to a version that resolves this vulnerability.

    Fixed in 0:7.78.0-3.jbcs.el7
  11. Upgrade

    Upgrade redhat/jbcs-httpd24-httpd to a version that resolves this vulnerability.

    Fixed in 0:2.4.37-80.jbcs.el7
  12. Upgrade

    Upgrade redhat/jbcs-httpd24-nghttp2 to a version that resolves this vulnerability.

    Fixed in 0:1.39.2-41.jbcs.el7
  13. Upgrade

    Upgrade redhat/jbcs-httpd24-openssl to a version that resolves this vulnerability.

    Fixed in 1:1.1.1g-11.jbcs.el7
  14. Upgrade

    Upgrade redhat/jbcs-httpd24-openssl-chil to a version that resolves this vulnerability.

    Fixed in 0:1.0.0-11.jbcs.el7
  15. Upgrade

    Upgrade redhat/jbcs-httpd24-openssl-pkcs11 to a version that resolves this vulnerability.

    Fixed in 0:0.4.10-26.jbcs.el7
  16. Upgrade

    Upgrade redhat/libxml2 to a version that resolves this vulnerability.

    Fixed in 0:2.9.7-9.el8_4.2
  17. Upgrade

    Upgrade Apple macOS to a version that resolves this vulnerability.

    Fixed in 11.5
  18. Upgrade

    Upgrade tvOS to a version that resolves this vulnerability.

    Fixed in 14.7
  19. Upgrade

    Upgrade Apple iOS, iPadOS, and watchOS to a version that resolves this vulnerability.

    Fixed in 7.6
  20. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 11.5
  21. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 14.7
  22. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 7.6
  23. Upgrade

    Upgrade redhat/libxml2 to a version that resolves this vulnerability.

    Fixed in 2.9.11
  24. Upgrade

    Upgrade libxml2 to a version that resolves this vulnerability.

    Fixed in 2.9.11
  25. Compensating control

    When processing untrusted files, ensure the application linked with libxml2 does not process attacker-supplied crafted files (e.g., validate/sandbox file handling before calling into libxml2), since a crafted file could trigger a use-after-free in xmlXIncludeDoProcess() (xinclude.c) leading to arbitrary code execution.

Event History

Apr 22, 2021
CVE Published
12:00 AM
Apr 27, 2021
Data Sourced
via Red Hat·07:03 PM
DescriptionSeverityAffected Software
May 18, 2021
CVE Published
via MITRE·11:20 AM
Data Sourced
via MITRE·11:20 AM
DescriptionWeakness
Data Sourced
via NVD·12:15 PM
RemedyDescriptionSeverityWeaknessAffected Software
Jul 19, 2021
Data Sourced
via Apple·12:00 AM
DescriptionWeaknessAffected Software
Updated
via Apple·12:00 AM
DescriptionWeakness
Updated
via Apple·12:00 AM
Affected Software
Updated
via Apple·12:00 AM
DescriptionWeaknessAffected Software
Jul 21, 2021
Updated
via Apple·12:00 AM
DescriptionWeaknessAffected Software
Updated
via Apple·12:00 AM
Affected Software
May 24, 2022
Advisory Published
07:02 PM
Feb 24, 2026
Updated
via Apple·07:00 PM
DescriptionWeaknessAffected Software
Updated
via Apple·07:00 PM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

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Frequently Asked Questions

1

What is CVE-2021-3518?

CVE-2021-3518 is a vulnerability in libxml2 before version 2.9.11 that allows an attacker to trigger a use-after-free by submitting a crafted file to an application linked with libxml2.

2

What is the impact of CVE-2021-3518?

The greatest impact of CVE-2021-3518 is to the confidentiality, integrity, and availability of the affected system.

3

Which software versions are affected by CVE-2021-3518?

CVE-2021-3518 affects Apple watchOS up to version 7.6, Apple tvOS up to version 14.7, Apple macOS Big Sur up to version 11.5, and various packages from Red Hat.

4

How can I fix CVE-2021-3518?

To fix CVE-2021-3518, update to libxml2 version 2.9.11 or later for Apple products, and apply the relevant patches or updates for Red Hat packages.

5

Where can I find more information about CVE-2021-3518?

You can find more information about CVE-2021-3518 on the Apple support website at the provided reference links.

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