What is CVE-2023-41034?

CVE-2023-41034 is a medium-severity vulnerability in Eclipse Leshan, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 6.5/10. Published 2023-08-31.

How severe is CVE-2023-41034?

Medium severity. CVSS v3 base score is 6.5 out of 10.

XXE in Eclipse Leshan

CVE-2023-41034

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.

Vulnerability class: XXE (XML External Entity)

Published 2023-08-31 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N.

EPSS exploit prediction

EPSS: 0.007 (51.1th percentile), scored 2026-10-04.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 51st percentile — 51.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: 0.000

Affected products

Eclipse Leshan — versions 2.0.0
Eclipse-Leshan Leshan — versions < 1.5.0, >= 2.0.0-M1, < 2.0.0-M13

Weakness classification (CWE)

CWE-611 — Improper Restriction of XML External Entity Reference (XXE)

References

github.com/eclipse-leshan/leshan/security/advisories/GHSA-wc9j-gc65-3cm7 (Third Party Advisory, Mitigation)
github.com/eclipse-leshan/leshan/commit/29577d2879ba8e7674c3b216a7f01193fc7ae013 (Patch)
github.com/eclipse-leshan/leshan/commit/4d3e63ac271a817f81fba3e3229c519af7a3049c (Patch)
github.com/eclipse-leshan/leshan/wiki/Adding-new-objects (Product)
owasp.org/www-community/vulnerabilities/XML_External_Entity_(XXE)_Processing (Not Applicable)

Frequently asked questions

What is CVE-2023-41034?: CVE-2023-41034 is a medium-severity vulnerability in Eclipse Leshan, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 6.5/10. Published 2023-08-31.
How severe is CVE-2023-41034?: Medium severity. CVSS v3 base score is 6.5 out of 10.