Orthanc DICOM Server has a heap buffer overflow that occurs while decoding PALETTE COLOR images. The decoder multiplies image width and height using 32‑bit arithmetic; if this multiplication overflows, the resulting pixel length validation incorrectly succeeds. The check fails to prevent the decoder from reading and writing beyond the allocated memory, allowing the attacker to overwrite adjacent heap objects and potentially execute arbitrary code. The flaw involves a heap buffer overflow (CWE‑787).

Any installation of Orthanc DICOM Server may be affected because the CNA record lists the product without restricting to particular releases. Users should verify the version of Orthanc in use against vendor information and plan to upgrade once a patch addresses the buffer overflow.

The severity score of 9.8 classifies this issue as Critical, while the EPSS score of less than 1% indicates a low current likelihood of widespread exploitation. The vulnerability is not included in the CISA KEV catalog. The likely attack vector is remote, inferred from the fact that DICOM images are received over the network by the server’s DICOM service; an attacker can send a specially crafted pixel array to trigger the overflow.