NVD / CVE Program· CNA GitHub_M

CVE-2021-43859: Denial of Service by injecting highly recursive collections or maps in XStream

Noroxi assessment

Priority: Monitor (action score 32/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 7.9% (FIRST EPSS); higher than 94.7% of all records.
Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
According to CISA the attack is automatable: targets can be found by mass scanning.
Fixed version: libxstream-java (Debian:11) 1.4.15-3+deb11u3; libxstream-java (Debian:12) 1.4.19-1; libxstream-java (Debian:9) 1.4.11.1-1+deb9u5.
Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to libxstream-java (Debian:11) 1.4.15-3+deb11u3; libxstream-java (Debian:12) 1.4.19-1; libxstream-java (Debian:9) 1.4.11.1-1+deb9u5 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

XStream is an open source java library to serialize objects to XML and back again. Versions prior to 1.4.19 may allow a remote attacker to allocate 100% CPU time on the target system depending on CPU type or parallel execution of such a payload resulting in a denial of service only by manipulating the processed input stream. XStream 1.4.19 monitors and accumulates the time it takes to add elements to collections and throws an exception if a set threshold is exceeded. Users are advised to upgrade as soon as possible. Users unable to upgrade may set the NO_REFERENCE mode to prevent recursion. See GHSA-rmr5-cpv2-vgjf for further details on a workaround if an upgrade is not possible.

HighCVSS 7.5 · v3.1—No exploit Fix available

Published: Feb 1, 2022
Updated: Jun 17, 2026
EPSS: 7.9% · 94th percentile
CWE: CWE-400

Report tools

JSON

Action score

Monitor

Low priority for now.

CVSS: 30 / 40 · 7.5 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 2 / 30 · 7.9%

CISA SSVC decision

Exploitation: proof of concept
Automatable: yes
Technical impact: partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: 7.5
CNA · GitHub_M: 7.5; agree

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

Not in KEV: no record of exploitation in the wild
No public exploit code on record
A fix has been released

If any of these changes, we'll tell you in the daily email digest.

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
xstream	xstream	cpe:2.3:a:xstream:xstream
jenkins	jenkins	cpe:2.3:a:jenkins:jenkins
fedoraproject	fedora	cpe:2.3:o:fedoraproject:fedora
debian	debian linux	cpe:2.3:o:debian:debian_linux
oracle	commerce guided search	cpe:2.3:a:oracle:commerce_guided_search
oracle	communications brm - elastic charging engine	cpe:2.3:a:oracle:communications_brm_-_elastic_charging_engine
oracle	communications cloud native core automated test suite	cpe:2.3:a:oracle:communications_cloud_native_core_automated_test_suite
oracle	communications diameter intelligence hub	cpe:2.3:a:oracle:communications_diameter_intelligence_hub
oracle	communications policy management	cpe:2.3:a:oracle:communications_policy_management
oracle	flexcube private banking	cpe:2.3:a:oracle:flexcube_private_banking
oracle	retail xstore point of service	cpe:2.3:a:oracle:retail_xstore_point_of_service

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

debian debian linux9.0
fedoraproject fedora34
fedoraproject fedora35
jenkins jenkins2.321 and later · before 2.334
jenkins jenkinsbefore 2.319.3
oracle commerce guided search11.3.2
oracle communications brm - elastic charging enginebefore 12.0.0.4.6
oracle communications brm - elastic charging engine12.0.0.5.0
oracle communications cloud native core automated test suite1.9.0
oracle communications diameter intelligence hub8.0.0 and later · up to 8.1.0 inclusive
oracle communications diameter intelligence hub8.2.0 and later · up to 8.2.6 inclusive
oracle communications policy management12.6.0.0.0
oracle flexcube private banking12.1.0
oracle retail xstore point of service16.0.6
oracle retail xstore point of service17.0.4
oracle retail xstore point of service18.0.3
oracle retail xstore point of service19.0.2
oracle retail xstore point of service20.0.1
xstream xstreambefore 1.4.19

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

x-stream xstream
- < 1.4.19affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Ecosystem	Package	Affected range	Fix
Debian:11	libxstream-java	before 1.4.15-3+deb11u3	1.4.15-3+deb11u3
Debian:12	libxstream-java	before 1.4.19-1	1.4.19-1
Debian:9	libxstream-java	before 1.4.11.1-1+deb9u5	1.4.11.1-1+deb9u5
Maven	com.thoughtworks.xstream:xstream	before 1.4.19	1.4.19
openSUSE:Leap 15.3	xstream	before 1.4.19-3.18.2	1.4.19-3.18.2
openSUSE:Tumbleweed	xstream	before 1.4.19-1.1	1.4.19-1.1
Red Hat:openshift:3.11::el7	jenkins	before 0:2.319.3.1650348949-1.el7	0:2.319.3.1650348949-1.el7
Red Hat:openshift:3.11::el7	jenkins-2-plugins	before 0:3.11.1650371376-1.el7	0:3.11.1650371376-1.el7
SUSE:Linux Enterprise Module for Development Tools 15 SP3	xstream	before 1.4.19-3.18.2	1.4.19-3.18.2

Same product

xstream: all records

Other highest-scoring records for the same primary product.

CVE-2021-39144XStream is vulnerable to a Remote Command Execution attackKEV
93Now
CVE-2019-10173It was found that xstream API version 1.4.10 before 1.4.11 introduced a regression for a previous deserialization flaw.
68This week
CVE-2013-7285Xstream API versions up to 1.4.6 and version 1.4.10, if the security framework has not been initialized, may allow a remote attacker to run
64This week

Published before and after this one in the same product

← EarlierCVE-2021-39150Aug 23, 2021 · A Server-Side Forgery Request vulnerability in XStream via PriorityQueue unmarshaling
35Monitor
← EarlierCVE-2021-39152Aug 23, 2021 · A Server-Side Forgery Request vulnerability in XStream via HashMap unmarshaling
37Monitor
Later →CVE-2022-40151Sep 16, 2022 · Stack Buffer Overflow in xstream
31Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
debian:libxstream-java	1.4.19-1 · Debian:12	Package registry (OSV)
Maven:com.thoughtworks.xstream:xstream	1.4.19	Package registry (OSV)
opensuse:xstream	1.4.19-3.18.2 · openSUSE:Leap 15.3	Package registry (OSV)
red hat:jenkins	0:2.319.3.1650348949-1.el7 · Red Hat:openshift:3.11::el7	Package registry (OSV)
red hat:jenkins-2-plugins	0:3.11.1650371376-1.el7 · Red Hat:openshift:3.11::el7	Package registry (OSV)
suse:xstream	1.4.19-3.18.2 · SUSE:Linux Enterprise Module for Development Tools 15 SP3	Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

x-stream/xstreamcommit e8e8862

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

TR-22-0271 · Mar 31, 2022(IBM Güvenlik Bildirimi)

All national notices →

Technical details

Attack conditions

Anyone who can reach it over the internet can trigger it.
No account or password is required.
No user action is required.
No special conditions are required; it is repeatable.

If successful

Confidentiality: none
Integrity: none
Availability: high · the service can be disrupted

Attack vector: Network
Attack complexity: Low
Privileges required: None
User interaction: None
Scope: Unchanged
Confidentiality impact: None
Integrity impact: None
Availability impact: High

Weakness class (CWE)

CWE-400 · Uncontrolled Resource Consumption

CVSS vector

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

nvd-primary

Root cause

Code that parses nested structures sets no depth or size limit. A small input can turn into a disproportionate processing load.

The bug in code

The whole CWE-400 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1function expand(node) {
2  return node.children.map(expand);
3}

Fixed

1const MAX_DEPTH = 32;
2function expand(node, depth = 0) {
3  if (depth > MAX_DEPTH) throw new Error("too deep");
4  return node.children.map((c) => expand(c, depth + 1));
5}

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Attack patterns (CAPEC)

ATT&CK techniques

Endpoint Denial of ServiceT1499

Change log

Fix✗ → ✓Sep 28, 2026, 10:45 PM UTC

For records you follow, these changes also arrive as notifications. →

References

www.openwall.com/lists/oss-security/2022/02/09/1

Show all references (7 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records