CVE-2021-43859

Public Exploit
Denial of Service by injecting highly recursive collections or maps in XStream

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.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 5.17% Top 15%
Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory github.io
Affected: x-stream xstream
Published at:
Updated at:

References

Link Tags
https://github.com/x-stream/xstream/security/advisories/GHSA-rmr5-cpv2-vgjf third party advisory exploit
https://github.com/x-stream/xstream/commit/e8e88621ba1c85ac3b8620337dd672e0c0c3a846 patch third party advisory
https://x-stream.github.io/CVE-2021-43859.html exploit vendor advisory
http://www.openwall.com/lists/oss-security/2022/02/09/1 third party advisory mailing list
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XODFRE2ZL64FICBJDOPWOLPTSSAI4U7X/ vendor advisory mailing list
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VACQYG356OHUTD5WQGAQ4L2TTFTAV3SJ/ vendor advisory mailing list
https://lists.debian.org/debian-lts-announce/2022/02/msg00018.html third party advisory mailing list
https://www.oracle.com/security-alerts/cpuapr2022.html patch third party advisory
https://www.oracle.com/security-alerts/cpujul2022.html patch third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-43859?
CVE-2021-43859 has been scored as a high severity vulnerability.
How to fix CVE-2021-43859?
To fix CVE-2021-43859, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-43859 being actively exploited in the wild?
It is possible that CVE-2021-43859 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~5% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-43859?
CVE-2021-43859 affects x-stream xstream.
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