CVE-2021-43859

unknown
Published 2022-02-01 · Modified 2026-03-13
CVSS v3
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v2
VIR risk

Description

XStream is an open source java library to serialize objects to XML and back again. Versions prior to 1.4.19 may allow a remote attacker to allocate 100% CPU time on the target system depending on CPU type or parallel execution of such a payload resulting in a denial of service only by manipulating the processed input stream. XStream 1.4.19 monitors and accumulates the time it takes to add elements to collections and throws an exception if a set threshold is exceeded. Users are advised to upgrade as soon as possible. Users unable to upgrade may set the NO_REFERENCE mode to prevent recursion. See GHSA-rmr5-cpv2-vgjf for further details on a workaround if an upgrade is not possible.

Predictions

Exploit likelihood
30%
Patch ETA

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

vendor Authored 2026-05-27

Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2021-43859

vendor Authored 2026-05-27

Vendor advisory: suse — https://www.suse.com/security/cve/CVE-2021-43859.html

OS impact

OSVersionStatusFixed in
suse slesaffected
debian debianbookwormfixed1.4.19-1
debian debianbullseyefixed1.4.15-3+deb11u3
debian debianforkyfixed1.4.19-1
debian debiansidfixed1.4.19-1
debian debiantrixiefixed1.4.19-1

Package impact

EcosystemPackageVulnerableFixed
java Mavencom.thoughtworks.xstream:xstream<1.4.191.4.19

References

Verify integrity in audit chain (admin only). AS-IS.