CVE-2021-21349

XStream is a Java library to serialize objects to XML and back again. In XStream before version 1.4.16, there is a vulnerability which may allow a remote attacker to request data from internal resources that are not publicly available only by manipulating the processed input stream. 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-502
• CWE-918
• CWE-918

• http://x-stream.github.io/changes.html#1.4.16Release Notes, Third Party Advisory
• https://github.com/x-stream/xstream/security/advisories/GHSA-f6hm-88x3-mfjvThird 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-2021-21349.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-f6hm-88x3-mfjvThird 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-2021-21349.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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