CVE-2021-21348

XStream is vulnerable to an attack using Regular Expression for a Denial of Service (ReDos)

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.

Category

5.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.19%
Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory debian.org Vendor Advisory oracle.com
Affected: x-stream xstream
Published at:
Updated at:

References

Link Tags
https://x-stream.github.io/security.html#workaround mitigation third party advisory
http://x-stream.github.io/changes.html#1.4.16 release notes third party advisory
https://github.com/x-stream/xstream/security/advisories/GHSA-56p8-3fh9-4cvq third party advisory
https://x-stream.github.io/CVE-2021-21348.html third party advisory
https://lists.debian.org/debian-lts-announce/2021/04/msg00002.html mailing list third party advisory
https://lists.apache.org/thread.html/r9ac71b047767205aa22e3a08cb33f3e0586de6b2fac48b425c6e16b0%40%3Cdev.jmeter.apache.org%3E mailing list issue tracking third party advisory
https://lists.apache.org/thread.html/r8244fd0831db894d5e89911ded9c72196d395a90ae655414d23ed0dd%40%3Cusers.activemq.apache.org%3E mailing list issue tracking third party advisory
https://security.netapp.com/advisory/ntap-20210430-0002/ third party advisory
https://www.oracle.com//security-alerts/cpujul2021.html third party advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/22KVR6B5IZP3BGQ3HPWIO2FWWCKT3DHP/ third party advisory mailing list vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QGXIU3YDPG6OGTDHMBLAFN7BPBERXREB/ third party advisory mailing list vendor advisory
https://www.oracle.com/security-alerts/cpuoct2021.html third party advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PVPHZA7VW2RRSDCOIPP2W6O5ND254TU7/ third party advisory mailing list vendor advisory
https://www.debian.org/security/2021/dsa-5004 third party advisory mailing list vendor advisory
https://www.oracle.com/security-alerts/cpujan2022.html patch vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-21348?
CVE-2021-21348 has been scored as a medium severity vulnerability.
How to fix CVE-2021-21348?
To fix CVE-2021-21348, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-21348 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-21348 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-21348?
CVE-2021-21348 affects x-stream xstream.
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