CVE-2021-21348
In XStream before version 1.4.16, there is a vulnerability which may allow a remote attacker to occupy a thread that consumes maximum CPU time and will never return.
Does this matter?
EPSS puts the probability of exploitation in the next 30 days at 13.8%, higher than 96% 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 occupy a thread that consumes maximum CPU time and will never return. 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
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 13.83% probability · 96th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-400, 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/mysql server · oracle/retail xstore point of service · oracle/webcenter portal
- Source
- security-advisories@github.com
EPSS 13.8% 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-56p8-3fh9-4cvqThird 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-2021-21348.htmlThird 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-56p8-3fh9-4cvqThird 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-2021-21348.htmlThird 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.