{"id":"CVE-2026-81875","state":"PUBLISHED","title":"HAPI FHIR: SHCParser unbounded DEFLATE decompression causes denial of service","description":"HAPI FHIR is a complete implementation of the HL7 FHIR standard for healthcare interoperability in Java. Prior to version 6.9.12, SHCParser in org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/elementmodel/SHCParser.java can consume attacker-controlled Smart Health Card JWT content whose header contains zip: \"DEF\" and whose small raw-DEFLATE payload expands to a very large value. SHCParser.decodeJWT() passes the decoded payload to SHCParser.inflate(), which accumulates all decompressed bytes in a ByteArrayOutputStream without an output-size limit before JSON parsing, and SHCParser.decompress() contains the same unbounded pattern. An application or validator service that accepts attacker-supplied SHC content can therefore suffer excessive heap allocation, severe garbage-collection pressure, request failure, process instability, or process termination. This issue is fixed in version 6.9.12.","publishedAt":"2026-09-16T18:44:47.591Z","updatedAt":"2026-09-17T16:14:31.374Z","severity":{"score":7.5,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","source":"GitHub_M"},"assigner":"GitHub_M","products":["hapifhir org.hl7.fhir.core"],"affected":[{"vendor":"hapifhir","product":"org.hl7.fhir.core","versions":[{"version":"< 6.9.12","status":"affected"}]}],"references":["https://github.com/hapifhir/org.hl7.fhir.core/security/advisories/GHSA-3w98-rrpr-fprr","https://github.com/hapifhir/org.hl7.fhir.core/pull/2493","https://github.com/hapifhir/org.hl7.fhir.core/commit/fbb94216e0ad21ded75be77e5e20242ba194e83f","https://github.com/hapifhir/org.hl7.fhir.core/releases/tag/6.9.11","https://github.com/hapifhir/org.hl7.fhir.core/releases/tag/6.9.12"],"weaknesses":["CWE-20","CWE-400","CWE-409"],"ingestedAt":"2026-10-29T20:13:15.269Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/81xxx/CVE-2026-81875.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-81875","state":"PUBLISHED","datePublished":"2026-09-16T18:44:47.591Z","dateUpdated":"2026-09-17T16:14:31.374Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-08-27T17:48:42.121Z"},"containers":{"cna":{"title":"HAPI FHIR: SHCParser unbounded DEFLATE decompression causes denial of service","descriptions":[{"lang":"en","value":"HAPI FHIR is a complete implementation of the HL7 FHIR standard for healthcare interoperability in Java. Prior to version 6.9.12, SHCParser in org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/elementmodel/SHCParser.java can consume attacker-controlled Smart Health Card JWT content whose header contains zip: \"DEF\" and whose small raw-DEFLATE payload expands to a very large value. SHCParser.decodeJWT() passes the decoded payload to SHCParser.inflate(), which accumulates all decompressed bytes in a ByteArrayOutputStream without an output-size limit before JSON parsing, and SHCParser.decompress() contains the same unbounded pattern. An application or validator service that accepts attacker-supplied SHC content can therefore suffer excessive heap allocation, severe garbage-collection pressure, request failure, process instability, or process termination. This issue is fixed in version 6.9.12."}],"affected":[{"vendor":"hapifhir","product":"org.hl7.fhir.core","versions":[{"version":"< 6.9.12","status":"affected"}]}],"references":[{"url":"https://github.com/hapifhir/org.hl7.fhir.core/security/advisories/GHSA-3w98-rrpr-fprr","name":"https://github.com/hapifhir/org.hl7.fhir.core/security/advisories/GHSA-3w98-rrpr-fprr","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/hapifhir/org.hl7.fhir.core/pull/2493","name":"https://github.com/hapifhir/org.hl7.fhir.core/pull/2493","tags":["x_refsource_MISC"]},{"url":"https://github.com/hapifhir/org.hl7.fhir.core/commit/fbb94216e0ad21ded75be77e5e20242ba194e83f","name":"https://github.com/hapifhir/org.hl7.fhir.core/commit/fbb94216e0ad21ded75be77e5e20242ba194e83f","tags":["x_refsource_MISC"]},{"url":"https://github.com/hapifhir/org.hl7.fhir.core/releases/tag/6.9.11","name":"https://github.com/hapifhir/org.hl7.fhir.core/releases/tag/6.9.11","tags":["x_refsource_MISC"]},{"url":"https://github.com/hapifhir/org.hl7.fhir.core/releases/tag/6.9.12","name":"https://github.com/hapifhir/org.hl7.fhir.core/releases/tag/6.9.12","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-20","lang":"en","description":"CWE-20: Improper Input Validation","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-400","lang":"en","description":"CWE-400: Uncontrolled Resource Consumption","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-409","lang":"en","description":"CWE-409: Improper Handling of Highly Compressed Data (Data Amplification)","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-09-16T18:44:47.591Z"},"source":{"advisory":"GHSA-3w98-rrpr-fprr","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/hapifhir/org.hl7.fhir.core/security/advisories/GHSA-3w98-rrpr-fprr","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-17T16:14:08.266567Z","id":"CVE-2026-81875","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-09-17T16:14:31.374Z"}}]}}}