CVE-2021-21347
In XStream before version 1.4.16, there is a vulnerability which may allow a remote attacker to load and execute arbitrary code from a remote host only by manipulating the processed input stream.
Does this matter?
EPSS puts the probability of exploitation in the next 30 days at 14.3%, higher than 97% of all known CVEs. Patch or mitigate before the next change window.
Description
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 load and execute arbitrary code from a remote host 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.
- CVSS 3.1
- 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 14.30% probability · 97th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-434, CWE-502
- Affected
- netapp/oncommand insight · apache/activemq · apache/jmeter · xstream/xstream · debian/debian linux · fedoraproject/fedora · oracle/banking enterprise default management · oracle/banking platform · oracle/banking virtual account management · oracle/business activity monitoring · oracle/communications billing and revenue management elastic charging engine · oracle/communications policy management · oracle/communications unified inventory management · oracle/retail xstore point of service · oracle/webcenter portal · oracle/weblogic server
- Source
- security-advisories@github.com
EPSS 14.3% since 26 October 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://x-stream.github.io/changes.html#1.4.16Release Notes, Third Party Advisory
- https://github.com/x-stream/xstream/security/advisories/GHSA-qpfq-ph7r-qv6fThird 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-2021-21347.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-qpfq-ph7r-qv6fThird 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-2021-21347.htmlExploit, Third Party Advisory
- https://x-stream.github.io/security.html#workaroundMitigation, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.