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Vulnerability record · CVE-2026-5445 · published 9 April 2026

CVE-2026-5445: Orthanc-server orthanc out-of-bounds read vulnerability

Orthanc Server · Orthanc

An out-of-bounds read vulnerability exists in the `DecodeLookupTable` function within `DicomImageDecoder.cpp`. The lookup-table decoding logic used for `PALETTE COLOR` images does not validate pixel indices against the lookup table size. Crafted images containing indices larger than the palette size cause the decoder to read beyond allocated lookup table memory and expose heap contents in the output image.

9.1 CVSS 3.1 Critical EPSS 0.79% · top 45.6% CWE-125 · Out-of-bounds read
9.1CVSS 3.1 base score
0.79%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
3References
17 Jun 2026Last modified by NVD

Description

An out-of-bounds read vulnerability exists in the `DecodeLookupTable` function within `DicomImageDecoder.cpp`. The lookup-table decoding logic used for `PALETTE COLOR` images does not validate pixel indices against the lookup table size. Crafted images containing indices larger than the palette size cause the decoder to read beyond allocated lookup table memory and expose heap contents in the output image.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://kb.cert.org/vuls/id/536588 Third Party AdvisoryVDB Entry
https://www.machinespirits.de/ Not Applicable
https://www.orthanc-server.com/ Product

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2026-5445), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.