Bug 1908837 (CVE-2020-26259)

Created xstream tracking bugs for this issue:

Affects: fedora-all [bug 1908838]

This vulnerability is out of security support scope for the following products:

 * Red Hat Data Grid 7
 * Red Hat JBoss BRMS 6
 * Red Hat JBoss BPMS 6
 * Red Hat JBoss Data Virtualization 6
 * Red Hat JBoss Fuse 6
 * Red Hat JBoss Fuse Service Works 6
 * Red Hat JBoss SOA Platform 5

Please refer to https://access.redhat.com/support/policy/updates/jboss_notes for more details.

Mitigation:

As recommended, use XStream's security framework to implement a whitelist for the allowed types.

Users of XStream 1.4.14 who insist to use XStream default blacklist - despite that clear recommendation - can simply add two lines to XStream's setup code:

xstream.denyTypes(new String[]{ "jdk.nashorn.internal.objects.NativeString" });
xstream.denyTypesByRegExp(new String[]{ ".*\\.ReadAllStream\\$FileStream" });

Users of XStream 1.4.13 who want to use XStream default blacklist can simply add three lines to XStream's setup code:

xstream.denyTypes(new String[]{ "javax.imageio.ImageIO$ContainsFilter", "jdk.nashorn.internal.objects.NativeString" });
xstream.denyTypes(new Class[]{ java.lang.ProcessBuilder.class });
xstream.denyTypesByRegExp(new String[]{ ".*\\.ReadAllStream\\$FileStream" });

Users of XStream 1.4.12 to 1.4.7 who want to use XStream with a blacklist will have to setup such a list from scratch and deny at least the following types: javax.imageio.ImageIO$ContainsFilter, java.beans.EventHandler, java.lang.ProcessBuilder, jdk.nashorn.internal.objects.NativeString, java.lang.Void and void and deny several types by name pattern.

xstream.denyTypes(new String[]{ "javax.imageio.ImageIO$ContainsFilter", "jdk.nashorn.internal.objects.NativeString" });
xstream.denyTypes(new Class[]{ java.lang.ProcessBuilder.class, java.beans.EventHandler.class, java.lang.ProcessBuilder.class, java.lang.Void.class, void.class });
xstream.denyTypesByRegExp(new String[]{ ".*\\$LazyIterator", "javax\\.crypto\\..*", ".*\\.ReadAllStream\\$FileStream" });

Users of XStream 1.4.6 or below can register an own converter to prevent the unmarshalling of the currently know critical types of the Java runtime. It is in fact an updated version of the workaround for CVE-2013-7285:

xstream.registerConverter(new Converter() {
  public boolean canConvert(Class type) {
    return type != null && (type == java.beans.EventHandler.class || type == java.lang.ProcessBuilder.class
        || type.getName().equals("javax.imageio.ImageIO$ContainsFilter") || type.getName().equals("jdk.nashorn.internal.objects.NativeString")
        || type == java.lang.Void.class || void.class || Proxy.isProxy(type)
        || type.getName().startsWith("javax.crypto.") || type.getName().endsWith("$LazyIterator") || type.getName().endsWith(".ReadAllStream$FileStream"));
  }

  public Object unmarshal(HierarchicalStreamReader reader, UnmarshallingContext context) {
    throw new ConversionException("Unsupported type due to security reasons.");
  }

  public void marshal(Object source, HierarchicalStreamWriter writer, MarshallingContext context) {
    throw new ConversionException("Unsupported type due to security reasons.");
  }
}, XStream.PRIORITY_LOW);

Upstream commit:
https://github.com/x-stream/xstream/commit/0bcbf50126a62dfcd65f93a0da0c6d1ae92aa738

Statement:

OpenShift Container Platform (OCP) delivers jenkins package with bundled XStream library. Due to JEP-200 Jenkins project [1] and advisory SECURITY-383 [2], OCP jenkins package is not affected by this flaw.

[1] https://github.com/jenkinsci/jep/blob/master/jep/200/README.adoc
[2] https://www.jenkins.io/security/advisory/2017-02-01/  (see SECURITY-383 / CVE-2017-2608)

This issue has been addressed in the following products:

  Red Hat Data Grid 8.2.0

Via RHSA-2021:2139 https://access.redhat.com/errata/RHSA-2021:2139

This bug is now closed. Further updates for individual products will be reflected on the CVE page(s):

https://access.redhat.com/security/cve/cve-2020-26259

This issue has been addressed in the following products:

  RHPAM 7.11.0

Via RHSA-2021:2475 https://access.redhat.com/errata/RHSA-2021:2475

This issue has been addressed in the following products:

  RHDM 7.11.0

Via RHSA-2021:2476 https://access.redhat.com/errata/RHSA-2021:2476

This issue has been addressed in the following products:

  Red Hat Integration

Via RHSA-2021:4767 https://access.redhat.com/errata/RHSA-2021:4767

This issue has been addressed in the following products:

  Red Hat Fuse 7.10

Via RHSA-2021:5134 https://access.redhat.com/errata/RHSA-2021:5134