Is CVE-2021-29505 in the CISA KEV catalog?

No. CVE-2021-29505 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2021-29505?

CVE-2021-29505 has a CVSS v3 base score of 7.5 (HIGH).

What is the EPSS score for CVE-2021-29505?

CVE-2021-29505 has an EPSS score of 77.73% (100th percentile), estimating the probability of exploitation in the next 30 days.

How do I fix CVE-2021-29505?

Upgrade libxstream-java on debian 11 to 1.4.15-3 or later.

CVE & CISA-KEV Catalog

CVE-2021-29505

HIGHEPSS 100th pctl

7.5

CVSS v3

NVD

Description

XStream is software for serializing Java objects to XML and back again. A vulnerability in XStream versions prior to 1.4.17 may allow a remote attacker has sufficient rights to execute commands of the host only by manipulating the processed input stream. No user who followed the recommendation to setup XStream's security framework with a whitelist limited to the minimal required types is affected. The vulnerability is patched in version 1.4.17.

CWE-94Code Injection CWE-502Deserialization of Untrusted Data

How to fix

Remediation Available

libxstream-javaDebian

Fixed in:1.4.15-3CVE-2021-29505

TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works

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 RequiredLow

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

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

Exploit Intelligence

77.73%probability of exploitation in 30 days

100thpercentile

Very high risk: more likely to be exploited than 100% of all known CVEs.

References

Patch3

Third-Party Advisory6

Issue Tracking1

lists.apache.org

Mailing List3

Other references7

Related Vulnerabilities

Other CWE-94 (Code Injection) vulnerabilities, ordered by exploit likelihood. View all

CVE	Severity	CVSS	EPSS	Exploited	Fix
CVE-2017-9841	Critical	9.8	100%	KEV	Fix
CVE-2015-1635	Critical	9.8	100%	KEV	-
CVE-2022-22954	Critical	9.8	100%	KEV + Ransom	-
CVE-2025-3248	Critical	9.8	100%	KEV + Ransom	Fix
CVE-2021-22204	Medium	6.8	100%	KEV	Fix
CVE-2012-0158	High	8.8	100%	KEV	-

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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 2025-05-30.