# CVE-2026-5442: A heap buffer overflow vulnerability exists in the DICOM image decoder. Dimension fields are encoded using Value…

Source: https://junglewise.ai/threats/cve-2026-5442-a-heap-buffer-overflow-vulnerability-exists-in-the-dicom-image  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-04-09  
License: CC BY 4.0 with a link back

CVE-2026-5442 · Severity: critical · CVSS 9.8 · Published 2026-04-09

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.

Technologies: [Orthanc-Server Orthanc](https://junglewise.ai/threats/technologies/orthanc-server-orthanc). Vendors: [Orthanc-Server](https://junglewise.ai/threats/vendors/orthanc-server).

## Quick answers

**Is CVE-2026-5442 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-5442 being exploited in the wild.

**How severe is CVE-2026-5442?** Critical severity, with a CVSS score of 9.8, published 9 April 2026.

**Which products and versions are affected?** Orthanc-Server Orthanc. The advisory does not name versions.

**Is there a fix for CVE-2026-5442?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**Am I affected by CVE-2026-5442?** Check whether you run Orthanc-Server Orthanc. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Affected products

- Orthanc-Server Orthanc

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