CVE-2022-25236: Critical severity Libexpat Project Libexpat vulnerability

Published Feb 16, 2022
·
Updated

A flaw was found in expat. Passing one or more namespace separator characters in the "xmlns[:prefix]" attribute values made expat send malformed tag names to the XML processor on top of expat. This issue causes arbitrary code execution depending on how unexpected cases are handled inside the XML processor.

Other sources

xmlparse.c in Expat (aka libexpat) before 2.4.5 allows attackers to insert namespace-separator characters into namespace URIs.

Affected Software

28 affected componentsFixes available
redhat/expat<0:2.0.1-14.el6_10
0:2.0.1-14.el6_10
redhat/firefox<0:91.7.0-3.el7_9
0:91.7.0-3.el7_9
redhat/thunderbird<0:91.7.0-2.el7_9
0:91.7.0-2.el7_9
redhat/expat<0:2.1.0-14.el7_9
0:2.1.0-14.el7_9
redhat/firefox<0:91.7.0-3.el8_5
0:91.7.0-3.el8_5
redhat/thunderbird<0:91.7.0-2.el8_5
0:91.7.0-2.el8_5
redhat/mingw-expat<0:2.4.8-1.el8
0:2.4.8-1.el8
redhat/expat<0:2.2.5-4.el8_5.3
0:2.2.5-4.el8_5.3
redhat/firefox<0:91.7.0-3.el8_1
0:91.7.0-3.el8_1
redhat/thunderbird<0:91.7.0-2.el8_1
0:91.7.0-2.el8_1
redhat/expat<0:2.2.5-3.el8_1.1
0:2.2.5-3.el8_1.1
redhat/firefox<0:91.7.0-3.el8_2
0:91.7.0-3.el8_2
redhat/thunderbird<0:91.7.0-2.el8_2
0:91.7.0-2.el8_2
redhat/expat<0:2.2.5-3.el8_2.2
0:2.2.5-3.el8_2.2
redhat/firefox<0:91.7.0-3.el8_4
0:91.7.0-3.el8_4
redhat/thunderbird<0:91.7.0-2.el8_4
0:91.7.0-2.el8_4
redhat/expat<0:2.2.5-4.el8_4.2
0:2.2.5-4.el8_4.2
redhat/redhat-virtualization-host<0:4.3.22-20220330.1.el7_9
0:4.3.22-20220330.1.el7_9
Libexpat Project Libexpat<2.4.5
Debian Debian Linux=10.0
Debian Debian Linux=11.0
Oracle HTTP Server=12.2.1.3.0
Oracle HTTP Server=12.2.1.4.0
Oracle ZFS Storage Appliance Kit=8.8
Siemens SINEMA Remote Connect Server<3.1
redhat/expat<2.4.5
2.4.5
debian/expat
2.2.10-2+deb11u52.2.10-2+deb11u72.5.0-1+deb12u22.5.0-1+deb12u12.7.1-22.8.1-1
debian/libxmltok<=1.2-4

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

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

    Fixed in 0:2.0.1-14.el6_10
  2. Upgrade

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

    Fixed in 0:91.7.0-3.el7_9
  3. Upgrade

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

    Fixed in 0:91.7.0-2.el7_9
  4. Upgrade

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

    Fixed in 0:2.1.0-14.el7_9
  5. Upgrade

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

    Fixed in 0:91.7.0-3.el8_5
  6. Upgrade

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

    Fixed in 0:91.7.0-2.el8_5
  7. Upgrade

    Upgrade redhat/mingw-expat to a version that resolves this vulnerability.

    Fixed in 0:2.4.8-1.el8
  8. Upgrade

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

    Fixed in 0:2.2.5-4.el8_5.3
  9. Upgrade

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

    Fixed in 0:91.7.0-3.el8_1
  10. Upgrade

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

    Fixed in 0:91.7.0-2.el8_1
  11. Upgrade

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

    Fixed in 0:2.2.5-3.el8_1.1
  12. Upgrade

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

    Fixed in 0:91.7.0-3.el8_2
  13. Upgrade

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

    Fixed in 0:91.7.0-2.el8_2
  14. Upgrade

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

    Fixed in 0:2.2.5-3.el8_2.2
  15. Upgrade

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

    Fixed in 0:91.7.0-3.el8_4
  16. Upgrade

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

    Fixed in 0:91.7.0-2.el8_4
  17. Upgrade

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

    Fixed in 0:2.2.5-4.el8_4.2
  18. Upgrade

    Upgrade redhat/redhat-virtualization-host to a version that resolves this vulnerability.

    Fixed in 0:4.3.22-20220330.1.el7_9
  19. Upgrade

    Upgrade debian/expat to a version that resolves this vulnerability.

    Fixed in 2.2.10-2+deb11u5Fixed in 2.2.10-2+deb11u7Fixed in 2.5.0-1+deb12u2Fixed in 2.5.0-1+deb12u1Fixed in 2.7.1-2Fixed in 2.8.1-1
  20. Upgrade

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

    Fixed in 2.4.5
  21. Upgrade

    Upgrade Expat (libexpat) to a version that resolves this vulnerability.

    Fixed in 2.4.5
  22. Compensating control

    Restrict applications using the expat (libexpat) library from processing untrusted XML content, since there is no known mitigation other than this restriction.

Event History

Feb 16, 2022
CVE Published
via MITRE·12:39 AM
Data Sourced
via MITRE·12:39 AM
Description
Data Sourced
09:39 PM
SeverityAffected Software
Feb 21, 2022
Data Sourced
via Red Hat·05:30 AM
DescriptionSeverityAffected Software
May 27, 2026
Data Sourced
via Launchpad·11:14 AM
Description
May 28, 2026
Data Sourced
via Ubuntu·11:13 AM
RemedyDescriptionSeverityAffected Software
Data Sourced
via Debian·11:15 AM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the vulnerability ID of this flaw in Expat?

The vulnerability ID of this flaw in Expat is CVE-2022-25236.

2

What is the severity level of CVE-2022-25236?

The severity level of CVE-2022-25236 is critical.

3

What is the affected software of CVE-2022-25236?

The affected software of CVE-2022-25236 includes Expat (libexpat) versions before 2.4.5, Red Hat, Firefox, Thunderbird, mingw-expat, and others.

4

How can an attacker exploit CVE-2022-25236?

An attacker can exploit CVE-2022-25236 by passing namespace separator characters in the "xmlns[:prefix]" attribute values, causing expat to send malformed tag names to the XML processor.

5

Where can I find more information about CVE-2022-25236?

You can find more information about CVE-2022-25236 at the following references: http://www.openwall.com/lists/oss-security/2022/02/19/1, https://github.com/libexpat/libexpat/pull/561, and https://bugzilla.redhat.com/show_bug.cgi/show_bug.cgi?id=2056371

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