What is CVE-2026-5442?

CVE-2026-5442 is a critical-severity vulnerability in Orthanc Dicom Server, classified under Out-of-bounds Write. CVSS score: 9.8/10. Published 2026-04-09.

How severe is CVE-2026-5442?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Buffer overflow in Orthanc Dicom Server

CVE-2026-5442

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 dimension…

Vulnerability class: Buffer Overflow

EPSS: 0.006 (44.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Orthanc Dicom Server — versions 0
Orthanc-server Orthanc

Weakness classification (CWE)

CWE-787 — Out-of-bounds Write

References

cret@cert.org (Product)
cret@cert.org (Not Applicable)
cret@cert.org (VDB Entry, Third Party Advisory)

Frequently asked questions

What is CVE-2026-5442?: CVE-2026-5442 is a critical-severity vulnerability in Orthanc Dicom Server, classified under Out-of-bounds Write. CVSS score: 9.8/10. Published 2026-04-09.
How severe is CVE-2026-5442?: Critical severity. CVSS v3 base score is 9.8 out of 10.