CVE-2026-45367: CWE-1333: Inefficient Regular Expression Complexity in hapifhir org.hl7.fhir.core
HAPI FHIR is a complete implementation of the HL7 FHIR standard for healthcare interoperability in Java. Prior to 6.9.7, the FHIRPathEngine implementation passes user-controlled regular expressions from matches(), matchesFull(), and replaceMatches() to Java regex operations without effective timeouts, allowing catastrophic backtracking and denial of service. This issue is fixed in version 6.9.7.
AI Analysis
Technical Summary
The vulnerability CVE-2026-45367 affects the HAPI FHIR library's org.hl7.fhir.core product, specifically the FHIRPathEngine implementation. User-supplied regular expressions used in matches(), matchesFull(), and replaceMatches() methods are processed without timeout constraints, allowing inefficient regular expression complexity (CWE-1333). This can cause catastrophic backtracking in Java regex processing, resulting in denial of service. The vulnerability is resolved in version 6.9.7.
Potential Impact
An attacker can supply crafted regular expressions that cause excessive processing time due to catastrophic backtracking, leading to denial of service conditions. There is no impact on confidentiality or integrity reported, only availability is affected.
Mitigation Recommendations
Upgrade to HAPI FHIR version 6.9.7 or later, where this vulnerability has been fixed. No other mitigation or temporary workaround is indicated.
CVE-2026-45367: CWE-1333: Inefficient Regular Expression Complexity in hapifhir org.hl7.fhir.core
Description
HAPI FHIR is a complete implementation of the HL7 FHIR standard for healthcare interoperability in Java. Prior to 6.9.7, the FHIRPathEngine implementation passes user-controlled regular expressions from matches(), matchesFull(), and replaceMatches() to Java regex operations without effective timeouts, allowing catastrophic backtracking and denial of service. This issue is fixed in version 6.9.7.
CVSS v3.1
Score 7.5high
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2026-45367 affects the HAPI FHIR library's org.hl7.fhir.core product, specifically the FHIRPathEngine implementation. User-supplied regular expressions used in matches(), matchesFull(), and replaceMatches() methods are processed without timeout constraints, allowing inefficient regular expression complexity (CWE-1333). This can cause catastrophic backtracking in Java regex processing, resulting in denial of service. The vulnerability is resolved in version 6.9.7.
Potential Impact
An attacker can supply crafted regular expressions that cause excessive processing time due to catastrophic backtracking, leading to denial of service conditions. There is no impact on confidentiality or integrity reported, only availability is affected.
Mitigation Recommendations
Upgrade to HAPI FHIR version 6.9.7 or later, where this vulnerability has been fixed. No other mitigation or temporary workaround is indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-05-12T00:51:29.085Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a590f0b68715ace43614ec2
Added to database: 07/16/2026, 17:04:11 UTC
Last enriched: 07/23/2026, 22:38:37 UTC
Last updated: 08/30/2026, 17:03:26 UTC
Views: 83
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