MITM based Zip Slip in `org.hl7.fhir.publisher:org.hl7.fhir.publisher`

Impact

MITM can enable Zip-Slip.

Vulnerability

Vulnerability 1: Publisher.java

There is no validation that the zip file being unpacked has entries that are not maliciously writing outside of the intended destination directory.

https://github.com/HL7/fhir-ig-publisher/blob/87313e92de6dd6cea816449e0edd225e054a7891/org.hl7.fhir.publisher.core/src/main/java/org/hl7/fhir/igtools/publisher/Publisher.java#L3598-L3610

Vulnerability 2: WebSourceProvider.java

There is a check for malicious zip entries here, but it is not covered by test cases and could potentially be reverted in future changes.

https://github.com/HL7/fhir-ig-publisher/blob/87313e92de6dd6cea816449e0edd225e054a7891/org.hl7.fhir.publisher.core/src/main/java/org/hl7/fhir/igtools/web/WebSourceProvider.java#L104-L112

Vulnerability 3: ZipFetcher.java

This retains the path for Zip files in FetchedFile entries, which could later be used to output malicious entries to another compressed file or file system.

https://github.com/HL7/fhir-ig-publisher/blob/87313e92de6dd6cea816449e0edd225e054a7891/org.hl7.fhir.publisher.core/src/main/java/org/hl7/fhir/igtools/publisher/ZipFetcher.java#L57-L106

Vulnerability 4: IGPack2NpmConvertor.java

The loadZip method retains the path for entries in the zip file, which could later be used to output malicious entries to another compressed file or file system.

https://github.com/HL7/fhir-ig-publisher/blob/87313e92de6dd6cea816449e0edd225e054a7891/org.hl7.fhir.publisher.core/src/main/java/org/hl7/fhir/igtools/publisher/IGPack2NpmConvertor.java#L442-L463