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CVE Vulnerabilities

CVE-2021-21342

Deserialization of Untrusted Data

Published: Mar 23, 2021 | Modified: May 23, 2025
CVSS 3.x
9.1
CRITICAL
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CVSS 2.x
5.8 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:N
RedHat/V2
RedHat/V3
7.4 MODERATE
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Ubuntu
MEDIUM
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Additional information
NVDhttps://nvd.nist.gov/vuln/detail/CVE-2021-21342
CWEhttps://cwe.mitre.org/data/definitions/502.html

XStream is a Java library to serialize objects to XML and back again. In XStream before version 1.4.16, there is a vulnerability where the processed stream at unmarshalling time contains type information to recreate the formerly written objects. XStream creates therefore new instances based on these type information. An attacker can manipulate the processed input stream and replace or inject objects, that result in a server-side forgery request. No user is affected, who followed the recommendation to setup XStreams security framework with a whitelist limited to the minimal required types. If you rely on XStreams default blacklist of the Security Framework, you will have to use at least version 1.4.16.

Weakness

The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.

Affected Software

NameVendorStart VersionEnd Version
Oncommand_insightNetapp- (including)- (including)
Red Hat Data Grid 8.2.0RedHatxstream*
Red Hat Fuse 7.10RedHatxstream*
Red Hat IntegrationRedHat*
Red Hat Integration Camel Quarkus 2RedHat*
RHDM 7.11.0RedHatxstream*
RHPAM 7.11.0RedHatxstream*
Libxstream-javaUbuntubionic*
Libxstream-javaUbuntudevel*
Libxstream-javaUbuntuesm-apps/bionic*
Libxstream-javaUbuntuesm-apps/focal*
Libxstream-javaUbuntuesm-apps/jammy*
Libxstream-javaUbuntuesm-apps/noble*
Libxstream-javaUbuntuesm-apps/xenial*
Libxstream-javaUbuntuesm-infra-legacy/trusty*
Libxstream-javaUbuntufocal*
Libxstream-javaUbuntugroovy*
Libxstream-javaUbuntuhirsute*
Libxstream-javaUbuntuimpish*
Libxstream-javaUbuntujammy*
Libxstream-javaUbuntukinetic*
Libxstream-javaUbuntulunar*
Libxstream-javaUbuntumantic*
Libxstream-javaUbuntunoble*
Libxstream-javaUbuntuoracular*
Libxstream-javaUbuntutrusty*
Libxstream-javaUbuntutrusty/esm*
Libxstream-javaUbuntuupstream*
Libxstream-javaUbuntuxenial*

Potential Mitigations

  • Make fields transient to protect them from deserialization.
  • An attempt to serialize and then deserialize a class containing transient fields will result in NULLs where the transient data should be. This is an excellent way to prevent time, environment-based, or sensitive variables from being carried over and used improperly.

References

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