GHSA-683x-4444-jxh8 is a high-severity (CVSS 7.5) XML External Entity (XXE) vulnerability in org.cyclonedx:cyclonedx-core-java. A fix is available for org.cyclonedx:cyclonedx-core-java — see the affected versions and patch details below.
Improper Restriction of XML External Entity Reference in org.cyclonedx:cyclonedx-core-java
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
Exploitation and automatability from CISA’s SSVC triage for GHSA-683x-4444-jxh8.
EPSS Exploitation Probability
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
GHSA-683x-4444-jxh8 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 379,145 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
org.cyclonedx:cyclonedx-core-javaReal-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
Impact
Before deserializing CycloneDX Bill of Materials in XML format, cyclonedx-core-java leverages XPath expressions to determine the schema version of the BOM. The DocumentBuilderFactory used to evaluate XPath expressions was not configured securely, making the library vulnerable to XML External Entity (XXE) injection.
XXE injection can be exploited to exfiltrate local file content, or perform Server Side Request Forgery (SSRF) to access infrastructure adjacent to the vulnerable application.
PoC
import org.cyclonedx.parsers.XmlParser;
class Poc {
public static void main(String[] args) {
// Will throw org.cyclonedx.exception.ParseException: java.net.ConnectException: Connection refused
new XmlParser().parse("""
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE bom [<!ENTITY % sp SYSTEM "https://localhost:1010/does-not-exist/file.dtd"> %sp;]>
<bom xmlns="http://cyclonedx.org/schema/bom/1.5"/>
""".getBytes());
}
}
Patches
The vulnerability has been fixed in cyclonedx-core-java version 0.9.4.
Workarounds
If feasible, applications can reject XML documents before handing them to cyclonedx-core-java for parsing. This may be an option if incoming CycloneDX BOMs are known to be in JSON format.
References
- Issue was fixed via https://github.com/CycloneDX/cyclonedx-core-java/pull/434
- Issue was introduced via https://github.com/CycloneDX/cyclonedx-core-java/commit/162aa594f347b3f612fe0a45071693c3cd398ce9
- https://owasp.org/www-community/vulnerabilities/XML_External_Entity_(XXE)_Processing
- https://cheatsheetseries.owasp.org/cheatsheets/XML_External_Entity_Prevention_Cheat_Sheet.html#xpathexpression
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.cyclonedx:cyclonedx-core-java | ≥ 2.1.0&&< 9.0.4 | 9.0.4org.cyclonedx:cyclonedx-core-java:9.0.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.cyclonedx:cyclonedx-core-java, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.cyclonedx:cyclonedx-core-java to 9.0.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-683x-4444-jxh8 is resolved across your whole dependency graph.
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.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-683x-4444-jxh8 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-683x-4444-jxh8. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-683x-4444-jxh8 in your dependencies?
O3 Security finds GHSA-683x-4444-jxh8 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.