CVE-2026-5442: critical vulnerability in Orthanc DICOM Server
Heap Buffer Overflow in DICOM Image Decoder via VR UL Dimensions
Published · Updated
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28Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 9.8epss 0.6%
A heap buffer overflow vulnerability exists in the DICOM image decoder. Dimension fields are encoded using Value Representation (VR) Unsigned Long (UL), instead of the expected VR Unsigned Short (US), which allows extremely large dimensions to be processed. This causes an integer overflow during frame size calculation and results in out-of-bounds memory access during image decoding.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
Orthanc · DICOM ServerRelated CVEs — Orthanc DICOM Server
In the same product, most dangerous first.
CVE-2026-5445CRITICALOut-of-Bounds Read in DicomImageDecoder (DecodeLookupTable)EPSS 0.7%CVE-2026-5437HIGHOut-of-Bounds Read in DicomStreamReaderEPSS 0.7%CVE-2026-5440HIGHMemory Exhaustion via Unbounded Content-LengthEPSS 0.6%CVE-2026-5443CRITICALHeap Buffer Overflow in DICOM Image Decoder (Palette Color Decode)EPSS 0.6%CVE-2026-87020HIGHOrthanc DICOM Server Integer Overflow or WraparoundEPSS 0.6%CVE-2026-5438HIGHGzip Decompression Bomb via Content-Encoding HeaderEPSS 0.5%