Server crash via unchecked DICOM value length
Published Apr 9, 2026 · Updated Apr 9, 2026
Out-of-bounds read in Orthanc DICOM Server 1.12.10 and earlier allows remote attackers to crash the server via crafted DICOM uploads. DicomStreamReader::HandleMetaHeader trusts each meta-header tag's declared value length and passes it to std::string::assign without confirming that the value remains inside the group-length-sized heap block. The vulnerable path is HTTP POST /instances; C-STORE regenerates meta-headers, and stock builds generally neither crash nor expose the extra bytes.
Summary
What happened
Out-of-bounds read in Orthanc DICOM Server 1.12.10 and earlier allows remote attackers to crash the server via crafted DICOM uploads. DicomStreamReader::HandleMetaHeader trusts each meta-header tag's declared value length and passes it to std::string::assign without confirming that the value remains inside the group-length-sized heap block. The vulnerable path is HTTP POST /instances; C-STORE regenerates meta-headers, and stock builds generally neither crash nor expose the extra bytes.
The record
- CVE
- CVE-2026-5437
- Published
- Apr 9, 2026
- Updated
- Apr 9, 2026
- Vendor
- Orthanc
- Product
- Orthanc
- Classifications
- CWE-125, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 9, 2026CVE publishedPublication date reported by the CVE source.
- Apr 9, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0 <=1.12.10
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
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Technologies
Your stack
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Your stack
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