`CVE-2023-41034` Eclipse Leshan

Affected software	Eclipse Leshan
Severity	9.8 Critical CVSS 3.1 2 scores
Fixed in	`1.5.0`, `2.0.0-M13`
Weakness	XML external entity (XXE) (CWE-611)
Published	31 Aug 2023
Updated	17 Jun 2026

Description

Eclipse Leshan is a device management server and client Java implementation. In affected versions DDFFileParser and DefaultDDFFileValidator (and so ObjectLoader) are vulnerable to XXE Attacks`. A DDF file is a LWM2M format used to store LWM2M object description. Leshan users are impacted only if they parse untrusted DDF files (e.g. if they let external users provide their own model), in that case they MUST upgrade to fixed version. If you parse only trusted DDF file and validate only with trusted xml schema, upgrading is not mandatory. This issue has been fixed in versions 1.5.0 and 2.0.0-M13. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Exploitation status

No public exploit

No exploit has been reported in the sources we check. Published 3 years ago.

CISA KEV not listed
VulnCheck KEV not listed
CISA Vulnrichment exploitation: none
Indexed PoC none indexed
EPSS 0.69% chance in 30 days

Waratek protection

Protected by Waratek

Waratek has a rule that blocks attacks on this vulnerability.

Protection full XXE
Action available security rule
Review automated Inferred
Record active

Decided by	A vulnerability class already blocked by an ARMR security rule
Finding	Protected by Waratek's ARMR xxe security rule, which blocks this class of attack at the JVM level without a rule written for this CVE specifically. The CVE's weakness is CWE-611: XML External Entity Reference.
Candidate fix	https://github.com/eclipse-leshan/leshan/commit/29577d2879ba8e7674c3b216a7f01193fc7ae013 : a commit: the change itself

Decided by

A vulnerability class already blocked by an ARMR security rule

Finding

Protected by Waratek's ARMR xxe security rule, which blocks this class of attack at the JVM level without a rule written for this CVE specifically. The CVE's weakness is CWE-611: XML External Entity Reference.

Candidate fix

https://github.com/eclipse-leshan/leshan/commit/29577d2879ba8e7674c3b216a7f01193fc7ae013 : a commit: the change itself

How to mitigate CVE-2023-41034

Upgrade Eclipse Leshan to a release that fixes it: 1.5.0 or 2.0.0-M13. Until you can, Waratek RASP blocks exploitation with its XXE rule. It runs inside the Java application, with no code changes.

Waratek RASP Runtime protection for Java applications

CVSS

9.8 CRITICAL v3.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H 2 metrics

We show the highest score from the newest CVSS version. Scores from different versions can't be compared, and the first score listed is sometimes a 0.0 placeholder.

Version Score Band Vector Assigner Type

CVSS 3.1 9.8 CRITICAL CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H NVD Primary published

CVSS 3.1 6.5 MEDIUM CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N security-advisories@github.com Secondary

Version	Score	Band	Vector	Assigner	Type
CVSS 3.1	9.8	CRITICAL	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`	NVD	Primary	published
CVSS 3.1	6.5	MEDIUM	`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N`	security-advisories@github.com	Secondary

Affected software and releases

Maven packages

Affected and fixed versions, from OSV.dev

Package Introduced Fixed Last affected

org.eclipse.leshan:leshan-core 0 1.5.0 unbounded

org.eclipse.leshan:leshan-core 2.0.0-M1 2.0.0-M13 unbounded

Package	Introduced	Fixed	Last affected
`org.eclipse.leshan:leshan-core`	0	`1.5.0`	unbounded
`org.eclipse.leshan:leshan-core`	2.0.0-M1	`2.0.0-M13`	unbounded

Products and versions

2 products, 15 version entries

Source	Vendor	Product	Scheme	Affected versions
nvd	eclipse	leshan	generic	＜ 1.5.0 · 2.0.0:milestone1 · 2.0.0:milestone10 · 2.0.0:milestone11 · 2.0.0:milestone12 · 2.0.0:milestone2 · 2.0.0:milestone3 · 2.0.0:milestone4 · 2.0.0:milestone5 · 2.0.0:milestone6 · 2.0.0:milestone7 · 2.0.0:milestone8 · 2.0.0:milestone9
osv	org.eclipse.leshan	leshan-core	generic	＜ 1.5.0 · ≥ 2.0.0 and ＜ 2.0.0

Source

Vendor

Product

Scheme

Affected versions

nvd

eclipse

leshan

generic

＜ 1.5.0 · 2.0.0:milestone1 · 2.0.0:milestone10 · 2.0.0:milestone11 · 2.0.0:milestone12 · 2.0.0:milestone2 · 2.0.0:milestone3 · 2.0.0:milestone4 · 2.0.0:milestone5 · 2.0.0:milestone6 · 2.0.0:milestone7 · 2.0.0:milestone8 · 2.0.0:milestone9

osv

org.eclipse.leshan

leshan-core

generic

＜ 1.5.0 · ≥ 2.0.0 and ＜ 2.0.0

References

URL	Tags
https://github.com/eclipse-leshan/leshan/commit/29577d2879ba8e7674c3b216a7f01193fc7ae013	commit
https://github.com/eclipse-leshan/leshan/security/advisories/GHSA-wc9j-gc65-3cm7	WEB
https://github.com/eclipse-leshan/leshan/commit/4d3e63ac271a817f81fba3e3229c519af7a3049c	WEB
https://github.com/eclipse-leshan/leshan	PACKAGE
https://github.com/eclipse-leshan/leshan/wiki/Adding-new-objects#the-lwm2m-model	WEB
https://owasp.org/www-community/vulnerabilities/XML_External_Entity_(XXE)_Processing	WEB

URL

Timeline

Published	2023-08-31	By the CVE Program.
NVD record modified	2026-06-17	NVD's own last-modified date for this record.

Published

2023-08-31

By the CVE Program.

NVD record modified

2026-06-17

NVD's own last-modified date for this record.

How VRT decided (17 of 24 rules ran)

17 of 24 rules ran. The rest didn't run because an earlier rule had already settled the CVE.

# Rule Outcome Status Detail

identity: Does this identifier describe a vulnerability at all? the first rule that matches decides

1 rejected no match CVE Program withdrawal of this identifier

scope: Is it a vulnerability Waratek protects? the first rule that matches decides

2 armr-patch-file no match An ARMR patch file on disk for this CVE

3 armr-secure-rule-file no match An ARMR security-rule template on disk for this CVE

4 manual-classification no match A researcher's recorded decision for this specific CVE

5 manual classification no match Manual classification of this CVE in the legacy dataset

6 non-java-upstream no match A root cause in non-Java code: an OS kernel, a C library, or a bundled runtime

7 oracle-component no match The defect being in a component of a tracked product the agent does not reach: JavaFX, the Java SE installer, the JInitiator browser plug-in, the native WebLogic proxy plug-in, or a native part of Oracle Application Server or Collaboration Suite (HTTP Server, Web Cache, Internet Directory, mail and calendar servers). Oracle gives these no CPE of their own and names them only in the description.

8 java-client-side no match Oracle's own risk-matrix note saying the CVE is reached only through untrusted code in the Java sandbox (applets, Web Start) or only through a client installation of Java, so a server running its own trusted code is not exposed

9 osv-maven matched In scope Maven packages: org.eclipse.leshan:leshan-core

10 cna-maven-package not reached An affected Maven artifact named by the CNA itself

11 known-cpe-product not reached An NVD CPE naming a product ARMR tracks

12 cna-cpe-product not reached A CPE the CNA published naming a tracked product. Oracle publishes these on advisory day, months before NVD.

13 oracle-advisory-family not reached A tracked product family named in Oracle's own risk matrix. CPE cannot carry a suite name, only a module.

14 cna-named-product not reached A tracked product named in words by the CVE's own CNA, on a record with no CPE yet. Apache and Eclipse publish these on advisory day, before NVD adds CPE data.

15 non-deployable-product not reached The only affected product being a sealed appliance image, where Java runs but no -javaagent can be attached

16 unmatched-product not reached No tracked product matched above, and none present at all

disposition: What do we do about one that is? every rule runs

17 patch-hint matched Mitigation candidate References include candidate fix URL (commit tier): https://github.com/eclipse-leshan/leshan/commit/29577d2879ba8e7674c3b216a7f01193fc7ae013

18 open-source-maven skipped The affected package being open source on Maven, so the fix can be read

19 poc-derivable skipped An indexed exploit clearing the evidence bar to reverse-engineer, where there is no source to read

20 no-exploit skipped Nothing to build a rule from yet: no published exploit, no CISA record of exploitation and no source-level change to read

21 secure-rule-match decided it matched Protected by Waratek CWE-611 (XML External Entity Reference) is mitigable by an ARMR xxe security rule.

22 exploited-no-fix-or-poc skipped Somebody exploiting this CVE (a CISA or VulnCheck KEV listing, or a CISA verdict of active exploitation), with no fix, source code or PoC to build a rule from

23 below-action-threshold skipped Medium or Low severity, no CISA or VulnCheck KEV listing, no PoC clearing the evidence bar, no CISA verdict, no Oracle advisory

24 no-exploit-published skipped Exploit code for this candidate, published in a reviewed catalogue or a GitHub repository with 5 or more stars, or in use per CISA or VulnCheck; not only a CISA verdict, a forecast, or nothing at all

Products the scope rules checked

The products this CVE's record names, and whether VRT tracks each one. The scope rules decided on these.

Vendor Product Tracked CPE Source

eclipse leshan not tracked cpe:2.3:a:eclipse:leshan:*:*:*:*:*:*:*:*

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