CVE-2023-23926 is a medium-severity (CVSS 5.9) vulnerability in org.neo4j.procedure:apoc-core. A fix is available for org.neo4j.procedure:apoc-core — see the affected versions and patch details below.
XML External Entity (XXE) vulnerability in apoc.import.graphml
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-2023-23926.
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
CVE-2023-23926 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 377,166 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.neo4j.procedure:apoc-core☕org.neo4j.procedure:apoc-coreReal-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
APOC (Awesome Procedures on Cypher) is an add-on library for Neo4j. An XML External Entity (XXE) vulnerability found in the apoc.import.graphml procedure of APOC core plugin prior to version 5.5.0 and 4.4.0.14 (4.4 branch) in Neo4j graph database. XML External Entity (XXE) injection occurs when the XML parser allows external entities to be resolved. The XML parser used by the apoc.import.graphml procedure was not configured in a secure way and therefore allowed this. External entities can be used to read local files, send HTTP requests, and perform denial-of-service attacks on the application. Abusing the XXE vulnerability enabled assessors to read local files remotely. Although with the level of privileges assessors had this was limited to one-line files. With the ability to write to the database, any file could have been read. Additionally, assessors noted, with local testing, the server could be crashed by passing in improperly formatted XML. The minimum version containing a patch for this vulnerability is 5.5.0. Those who cannot upgrade the library can control the allowlist of the procedures that can be used in your system.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.neo4j.procedure:apoc-core | ≥ 5.0.0&&< 5.5.0 | 5.5.0org.neo4j.procedure:apoc-core:5.5.0 |
| ☕Maven | org.neo4j.procedure:apoc-core | all versions | 4.4.0.14org.neo4j.procedure:apoc-core:4.4.0.14 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.neo4j.procedure:apoc-core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.neo4j.procedure:apoc-core to 5.5.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-23926 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 CVE-2023-23926 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2023-23926. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2023-23926 in your dependencies?
O3 Security finds CVE-2023-23926 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.