An integer overflow in a specified pitch and buffer-size computation leads to a heap out-of-bounds write when Orthanc DICOM Server decodes an… (CVE-2026-87020)

CVE-2026-87020 describes an integer overflow in Orthanc DICOM Server that occurs during the decoding of PNG images. The overflow affects the calculation of pitch and buffer size, which results in a heap out-of-bounds write. This memory corruption vulnerability can lead to integrity and availability impacts, such as application crashes or potential code execution. The vulnerability affects multiple specific versions of Orthanc DICOM Server as listed. The CVSS 3.1 base score is 8.1 with vector AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H, indicating network attack vector, low attack complexity, requiring low privileges, no user interaction, unchanged scope, no confidentiality impact, but high integrity and availability impact.

The vulnerability allows an attacker with low privileges to cause a heap out-of-bounds write by supplying a crafted PNG image to the Orthanc DICOM Server. This can lead to integrity and availability issues, such as application crashes or potentially arbitrary code execution. There is no direct confidentiality impact reported. No known exploits in the wild have been documented.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official patch or workaround details are provided in the available data. Users should monitor vendor communications for updates and apply any official fixes once available. Until then, restricting access to trusted users and validating input files may reduce risk.