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CVE-2026-81875 (GCVE-0-2026-81875)

Vulnerability from cvelistv5 – Published: 2026-09-16 18:44 – Updated: 2026-09-16 18:44
VLAI
Title
HAPI FHIR: SHCParser unbounded DEFLATE decompression causes denial of service
Summary
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-20 - Improper Input Validation
  • CWE-400 - Uncontrolled Resource Consumption
  • CWE-409 - Improper Handling of Highly Compressed Data (Data Amplification)
Assigner
References
Impacted products
Vendor Product Version CPE status
hapifhir org.hl7.fhir.core Affected: < 6.9.12
guessed Create a notification for this product.
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{
  "containers": {
    "cna": {
      "affected": [
        {
          "product": "org.hl7.fhir.core",
          "vendor": "hapifhir",
          "versions": [
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              "status": "affected",
              "version": "\u003c 6.9.12"
            }
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      ],
      "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."
        }
      ],
      "metrics": [
        {
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            "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",
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        {
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              "description": "CWE-400: Uncontrolled Resource Consumption",
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              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-409",
              "description": "CWE-409: Improper Handling of Highly Compressed Data (Data Amplification)",
              "lang": "en",
              "type": "CWE"
            }
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      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-16T18:44:47.591Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
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          "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/security/advisories/GHSA-3w98-rrpr-fprr"
        },
        {
          "name": "https://github.com/hapifhir/org.hl7.fhir.core/pull/2493",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/hapifhir/org.hl7.fhir.core/pull/2493"
        },
        {
          "name": "https://github.com/hapifhir/org.hl7.fhir.core/commit/fbb94216e0ad21ded75be77e5e20242ba194e83f",
          "tags": [
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          "url": "https://github.com/hapifhir/org.hl7.fhir.core/commit/fbb94216e0ad21ded75be77e5e20242ba194e83f"
        },
        {
          "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/6.9.11"
        },
        {
          "name": "https://github.com/hapifhir/org.hl7.fhir.core/releases/tag/6.9.12",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/hapifhir/org.hl7.fhir.core/releases/tag/6.9.12"
        }
      ],
      "source": {
        "advisory": "GHSA-3w98-rrpr-fprr",
        "discovery": "UNKNOWN"
      },
      "title": "HAPI FHIR: SHCParser unbounded DEFLATE decompression causes denial of service"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-81875",
    "datePublished": "2026-09-16T18:44:47.591Z",
    "dateReserved": "2026-08-27T17:48:42.121Z",
    "dateUpdated": "2026-09-16T18:44:47.591Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-81875\",\"sourceIdentifier\":\"security-advisories@github.com\",\"published\":\"2026-09-16T19:17:44.250\",\"lastModified\":\"2026-09-16T19:17:44.250\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"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\":[{\"source\":\"security-advisories@github.com\",\"affectedData\":[{\"vendor\":\"hapifhir\",\"product\":\"org.hl7.fhir.core\",\"versions\":[{\"version\":\"\u003c 6.9.12\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H\",\"baseScore\":7.5,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":3.9,\"impactScore\":3.6}]},\"weaknesses\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-20\"},{\"lang\":\"en\",\"value\":\"CWE-400\"},{\"lang\":\"en\",\"value\":\"CWE-409\"}]}],\"references\":[{\"url\":\"https://github.com/hapifhir/org.hl7.fhir.core/commit/fbb94216e0ad21ded75be77e5e20242ba194e83f\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/hapifhir/org.hl7.fhir.core/pull/2493\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/hapifhir/org.hl7.fhir.core/releases/tag/6.9.11\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/hapifhir/org.hl7.fhir.core/releases/tag/6.9.12\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/hapifhir/org.hl7.fhir.core/security/advisories/GHSA-3w98-rrpr-fprr\",\"source\":\"security-advisories@github.com\"}]}}"
  }
}



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