CVE-2021-21343

XStream is vulnerable to an Arbitrary File Deletion on the local host when unmarshalling as long as the executing process has sufficient rights

HIGH
7.5
CVSS Score
Published: March 22, 2021 at 11:40 PM UTC
Updated: October 7, 2026 at 07:17 PM UTC
15 products affected across 6 vendorsDebian LinuxFedoraOnCommand Insight

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Severity
HIGH7.5
Exploit prediction
EPSS 47%
SSVC
No known exploit

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 where the processed stream at unmarshalling time contains type information to recreate the formerly written objects. XStream creates therefore new instances based on these type information. An attacker can manipulate the processed input stream and replace or inject objects, that result in the deletion of a file on the local host. 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

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

References (15)

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
HIGH
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-73CWE-502NVD-CWE-noinfo

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