PoC Index85,100 CVEs with PoCs

CVE-2021-21351

XStream is vulnerable to an Arbitrary Code Execution attack

CRITICAL 9.1EPSS 82.1%

XStream is a Java library to serialize objects to XML and back again. In XStream before version 1.4.16, there is a vulnerability 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.

Affected
x-stream · xstream
CVSS v3.1 NVD
9.1 CRITICALCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
CVSS v3.1 GITHUB
5.4 MEDIUMCVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:C/C:N/I:H/A:N
CVSS v2.0 NVD
6.5 MEDIUMAV:N/AC:L/Au:S/C:P/I:P/A:P
EPSS
82.14% chance of exploitation in the next 30 days, 100th percentile
Nuclei
critical · CWE-434
Published
2021-03-22
Updated
2026-10-07

Nuclei templates (1)

Vulhub environments (1)

Security advisories

References