How severe is CVE-2023-28465?

CVE-2023-28465 has a CVSS score of 7.5/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2023-28465?

CVE-2023-28465 affects the following packages: ca.uhn.hapi.fhir:org.hl7.fhir.core (Maven), ca.uhn.hapi.fhir:org.hl7.fhir.convertors (Maven), ca.uhn.hapi.fhir:org.hl7.fhir.r4b (Maven), ca.uhn.hapi.fhir:org.hl7.fhir.r5 (Maven), ca.uhn.hapi.fhir:org.hl7.fhir.utilities (Maven), ca.uhn.hapi.fhir:org.hl7.fhir.validation (Maven). Ecosystems affected: Maven.

How do I fix CVE-2023-28465?

Update ca.uhn.hapi.fhir:org.hl7.fhir.core to 5.6.106 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-28465 is resolved across your whole dependency graph.

How do I detect CVE-2023-28465 in my Maven dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for ca.uhn.hapi.fhir:org.hl7.fhir.core. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate CVE-2023-28465 if there is no patch (or I can't update yet)?

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 does O3 Security protect against CVE-2023-28465?

O3 pinpoints whether CVE-2023-28465 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is CVE-2023-28465 actively exploited in the wild?

No public exploit code has been indexed for CVE-2023-28465 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2023-28465?

CVE-2023-28465 has an EPSS (Exploit Prediction Scoring System) score of 1.3%, placing it in the 67th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2023-28465?

CVE-2023-28465 is classified as Path Traversal (CWE-22). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2023-28465 published, and has it been updated?

CVE-2023-28465 was published on December 12, 2023 and was last updated on April 10, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

CVE-2023-28465: org.hl7.fhir.core Path Traversal (High 7.5)

EPSS Exploitation Probability

via FIRST.org ↗

1.3%probability of exploitation in next 30 days

Lower Risk67th percentile+0.56%

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.

Blast Radius

6 pkgs affected

☕ca.uhn.hapi.fhir:org.hl7.fhir.core☕ca.uhn.hapi.fhir:org.hl7.fhir.convertors☕ca.uhn.hapi.fhir:org.hl7.fhir.r4b☕ca.uhn.hapi.fhir:org.hl7.fhir.r5☕ca.uhn.hapi.fhir:org.hl7.fhir.utilities☕ca.uhn.hapi.fhir:org.hl7.fhir.validation

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

The package-decompression feature in HL7 (Health Level 7) FHIR Core Libraries before 5.6.106 allows attackers to copy arbitrary files to certain directories via directory traversal, if an allowed directory name is a substring of the directory name chosen by the attacker. NOTE: this issue exists because of an incomplete fix for CVE-2023-24057.

Affected Packages

6 total 6 fixed

Ecosystem	Package	Vulnerable range	Fix
☕Maven	`ca.uhn.hapi.fhir:org.hl7.fhir.core`	all versions	5.6.106
☕Maven	`ca.uhn.hapi.fhir:org.hl7.fhir.convertors`	all versions	5.6.106
☕Maven	`ca.uhn.hapi.fhir:org.hl7.fhir.r4b`	all versions	5.6.106
☕Maven	`ca.uhn.hapi.fhir:org.hl7.fhir.r5`	all versions	5.6.106
☕Maven	`ca.uhn.hapi.fhir:org.hl7.fhir.utilities`	all versions	5.6.106
☕Maven	`ca.uhn.hapi.fhir:org.hl7.fhir.validation`	all versions	5.6.106

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for ca.uhn.hapi.fhir:org.hl7.fhir.core. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update ca.uhn.hapi.fhir:org.hl7.fhir.core to 5.6.106 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-28465 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 pinpoints whether CVE-2023-28465 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to CVE-2023-28465. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

The package-decompression feature in HL7 (Health Level 7) FHIR Core Libraries before 5.6.106 allows attackers to copy arbitrary files to certain directories via directory traversal, if an allowed directory name is a substring of the directory name chosen by the attacker. NOTE: this issue exists because of an incomplete fix for CVE-2023-24057.

O3 Security · Impact-Aware SCA

Is CVE-2023-28465 in your dependencies?

O3 detects CVE-2023-28465 across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works

CVE-2023-28465