Buffer overflow in Orthanc Dicom Server
CVE-2026-5443
A heap buffer overflow vulnerability exists during the decoding of `PALETTE COLOR` DICOM images. Pixel length validation uses 32-bit multiplication for width and height calculations. If these values overflow, the validation check incorrectly succeeds, allowing the decoder to read and write to memory beyond allocated buffers.
Vulnerability class: Buffer Overflow
Published · last modified .
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.
EPSS exploit prediction
EPSS: 0.006 (46.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 47th percentile — 46.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.009 · newest: 0.006 · change: -0.003
Affected products
- Orthanc Dicom Server — versions 0
- Orthanc-Server Orthanc
Weakness classification (CWE)
References
- www.orthanc-server.com/ (Product)
- www.machinespirits.de/ (Not Applicable)
- kb.cert.org/vuls/id/536588 (VDB Entry, Third Party Advisory)
Frequently asked questions
- What is CVE-2026-5443?
- CVE-2026-5443 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-2026-5443?
- Critical severity. CVSS v3 base score is 9.8 out of 10.