CVE-2021-21343

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 the deletion of a file on the local host. No user is affected, who followed the recommendation to setup XStream's security framework with a whitelist limited to the minimal required types. If you rely on XStream's default blacklist of the Security Framework, you will have to use at least version 1.4.16.

• CWE-73
• CWE-502

• http://x-stream.github.io/changes.html#1.4.16Release Notes, Third Party Advisory
• https://github.com/x-stream/xstream/security/advisories/GHSA-74cv-f58x-f9wfThird Party Advisory
• https://lists.apache.org/thread.html/r8244fd0831db894d5e89911ded9c72196d395a90ae655414d23ed0dd%40%3Cusers.activemq.apache.org%3EIssue Tracking, Mailing List, Third Party Advisory
• https://lists.apache.org/thread.html/r9ac71b047767205aa22e3a08cb33f3e0586de6b2fac48b425c6e16b0%40%3Cdev.jmeter.apache.org%3EIssue Tracking, Mailing List, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2021/04/msg00002.htmlMailing List, Third Party Advisory
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/22KVR6B5IZP3BGQ3HPWIO2FWWCKT3DHP/Mailing List, Third Party Advisory
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PVPHZA7VW2RRSDCOIPP2W6O5ND254TU7/Mailing List, Third Party Advisory
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QGXIU3YDPG6OGTDHMBLAFN7BPBERXREB/Mailing List, Third Party Advisory
• https://security.netapp.com/advisory/ntap-20210430-0002/Third Party Advisory
• https://www.debian.org/security/2021/dsa-5004Mailing List, Third Party Advisory
• https://www.oracle.com//security-alerts/cpujul2021.htmlThird Party Advisory
• https://www.oracle.com/security-alerts/cpujan2022.htmlPatch, Vendor Advisory
• https://www.oracle.com/security-alerts/cpuoct2021.htmlThird Party Advisory
• https://x-stream.github.io/CVE-2021-21343.htmlExploit, Third Party Advisory
• https://x-stream.github.io/security.html#workaroundMitigation, Third Party Advisory
• http://x-stream.github.io/changes.html#1.4.16Release Notes, Third Party Advisory
• https://github.com/x-stream/xstream/security/advisories/GHSA-74cv-f58x-f9wfThird Party Advisory
• https://lists.apache.org/thread.html/r8244fd0831db894d5e89911ded9c72196d395a90ae655414d23ed0dd%40%3Cusers.activemq.apache.org%3EIssue Tracking, Mailing List, Third Party Advisory
• https://lists.apache.org/thread.html/r9ac71b047767205aa22e3a08cb33f3e0586de6b2fac48b425c6e16b0%40%3Cdev.jmeter.apache.org%3EIssue Tracking, Mailing List, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2021/04/msg00002.htmlMailing List, Third Party Advisory
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/22KVR6B5IZP3BGQ3HPWIO2FWWCKT3DHP/Mailing List, Third Party Advisory
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PVPHZA7VW2RRSDCOIPP2W6O5ND254TU7/Mailing List, Third Party Advisory
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QGXIU3YDPG6OGTDHMBLAFN7BPBERXREB/Mailing List, Third Party Advisory
• https://security.netapp.com/advisory/ntap-20210430-0002/Third Party Advisory
• https://www.debian.org/security/2021/dsa-5004Mailing List, Third Party Advisory
• https://www.oracle.com//security-alerts/cpujul2021.htmlThird Party Advisory
• https://www.oracle.com/security-alerts/cpujan2022.htmlPatch, Vendor Advisory
• https://www.oracle.com/security-alerts/cpuoct2021.htmlThird Party Advisory
• https://x-stream.github.io/CVE-2021-21343.htmlExploit, Third Party Advisory
• https://x-stream.github.io/security.html#workaroundMitigation, Third Party Advisory

Published

Mar 23, 2021

Last Modified

Jun 17, 2026

Status

Analyzed

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