CVE-2021-43859

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.

• CWE-400
• CWE-400

• http://www.openwall.com/lists/oss-security/2022/02/09/1Mailing List, Third Party Advisory
• https://github.com/x-stream/xstream/commit/e8e88621ba1c85ac3b8620337dd672e0c0c3a846Patch, Third Party Advisory
• https://github.com/x-stream/xstream/security/advisories/GHSA-rmr5-cpv2-vgjfExploit, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2022/02/msg00018.htmlMailing List, Third Party Advisory
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VACQYG356OHUTD5WQGAQ4L2TTFTAV3SJ/Mailing List
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XODFRE2ZL64FICBJDOPWOLPTSSAI4U7X/Mailing List
• https://www.oracle.com/security-alerts/cpuapr2022.htmlPatch, Third Party Advisory
• https://www.oracle.com/security-alerts/cpujul2022.htmlPatch, Third Party Advisory
• https://x-stream.github.io/CVE-2021-43859.htmlExploit, Vendor Advisory
• http://www.openwall.com/lists/oss-security/2022/02/09/1Mailing List, Third Party Advisory
• https://github.com/x-stream/xstream/commit/e8e88621ba1c85ac3b8620337dd672e0c0c3a846Patch, Third Party Advisory
• https://github.com/x-stream/xstream/security/advisories/GHSA-rmr5-cpv2-vgjfExploit, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2022/02/msg00018.htmlMailing List, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2024/12/msg00023.html
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VACQYG356OHUTD5WQGAQ4L2TTFTAV3SJ/Mailing List
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XODFRE2ZL64FICBJDOPWOLPTSSAI4U7X/Mailing List
• https://www.oracle.com/security-alerts/cpuapr2022.htmlPatch, Third Party Advisory
• https://www.oracle.com/security-alerts/cpujul2022.htmlPatch, Third Party Advisory
• https://x-stream.github.io/CVE-2021-43859.htmlExploit, Vendor Advisory

Published

Feb 1, 2022

Last Modified

Jun 17, 2026

Status

Modified

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