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Maven
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MEDIUM severity

CVE-2023-41034 leshan-core

MEDIUMFix: eclipse-leshan/leshan@29577d2

CVE-2023-41034 is a medium-severity (CVSS 6.5) XML External Entity (XXE) vulnerability in org.eclipse.leshan:leshan-core. A fix is available for org.eclipse.leshan:leshan-core — see the affected versions and patch details below.

DDFFileParser in eclipse leshan is vulnerable to XXE Attacks

Also known asGHSA-wc9j-gc65-3cm7
Published
Aug 31, 2023
Updated
Aug 12, 2026
Affected
2 pkgs
Patched
2 / 2
Exploits
None indexed
Exploitation data as of Sep 19, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

  • CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2023-41034.

EPSS Exploitation Probability

via FIRST.org ↗
0.7%probability of exploitation in next 30 days
Lower Risk0.00%
Lower risk than most CVEs51th percentile — riskier than 51% of all scored CVEsHighest risk

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

How urgent is this, really

CVE-2023-41034 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.

Where this sits among everything scored

Of 377,333 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.

Real-World Exposure

2 pkgs affected
org.eclipse.leshan:leshan-coreorg.eclipse.leshan:leshan-core

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.

Description

Eclipse Leshan is a device management server and client Java implementation. In affected versions DDFFileParserandDefaultDDFFileValidator(and soObjectLoader) 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.

Affected Packages

2 total 2 fixed
EcosystemPackageVulnerable rangeFix
Mavenorg.eclipse.leshan:leshan-coreall versions1.5.0org.eclipse.leshan:leshan-core:1.5.0
Mavenorg.eclipse.leshan:leshan-core2.0.0-M1&&< 2.0.0-M132.0.0-M13org.eclipse.leshan:leshan-core:2.0.0-M13

Detection & mitigation playbook

Open-source dependency
  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.eclipse.leshan:leshan-core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

  2. Fix

    Update org.eclipse.leshan:leshan-core to 1.5.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-41034 is resolved across your whole dependency graph.

  3. Workarounds

    If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

  4. How O3 protects you

    O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2023-41034 can be triaged on real exposure rather than presence alone.

Tailored to CVE-2023-41034. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

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
O3 Security · Impact-Aware SCA

Is CVE-2023-41034 in your dependencies?

O3 Security finds CVE-2023-41034 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.

CVE-2023-41034: leshan-core (Medium 6.5) | O3 Security