CVE & CISA-KEV Catalog

CVE-2021-21343

MEDIUMEPSS 99th pctl
5.3
CVSS v3
NVD

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.

How to fix

Remediation Available
libxstream-javaDebian
Fixed in:1.4.15-2CVE-2021-21343
Fixed in:1.4.15-2CVE-2021-21343
Fixed in:1.4.15-2CVE-2021-21343
Fixed in:1.4.15-2CVE-2021-21343
libxstream-javaUbuntu
Fixed in:1.4.7-1ubuntu0.1+esm2USN-6978-1
Fixed in:1.4.8-1ubuntu0.1+esm3USN-6978-1
Fixed in:1.4.11.1-1~18.04.2USN-4943-1
Fixed in:1.4.11.1-1ubuntu0.2USN-4943-1
Apache JMeterWindows application
Affected:5.5Fixed in:5.5DEVCOM

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Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork
Attack ComplexityHigh
Privileges RequiredNone
User InteractionRequired
ScopeUnchanged

Impact

ConfidentialityNone
IntegrityHigh
AvailabilityNone

CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N

Exploit Intelligence

46.67%probability of exploitation in 30 days
99thpercentile

Very high risk: more likely to be exploited than 99% of all known CVEs.

References

Related Vulnerabilities

Other CWE-73 (External Control of File Name or Path) vulnerabilities, ordered by exploit likelihood. View all

CVESeverityCVSSEPSSExploitedFix
CVE-2022-39952Critical9.8100%-Fix
CVE-2024-8517Critical9.895%-Fix
CVE-2023-4634Critical9.883%-Fix
CVE-2018-17246Critical9.882%-Fix
CVE-2025-33053High8.882%KEVFix
CVE-2024-43451Medium6.582%KEVFix
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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2025-05-23.