Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:HCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2026-5445 is a critical-severity Out-of-bounds Read (CWE-125) vulnerability in Orthanc-Server Orthanc. Its CVSS base score is 9.1 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked in the top 50% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SA-8 (Security and Privacy Engineering Principles) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2026-5445 is an out-of-bounds read vulnerability (CWE-125) in the DecodeLookupTable function within DicomImageDecoder.cpp, part of DICOM image processing software such as Orthanc server. The issue arises in the lookup-table decoding logic for PALETTE COLOR images, where pixel indices are not validated against the lookup table size. Processing crafted images with indices exceeding the palette size results in reads beyond allocated lookup table memory, exposing heap contents in the output image. Published on 2026-04-09, it carries a CVSS v3.1 base score of 9.1 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H).
Remote attackers require no privileges or user interaction to exploit this vulnerability over the network with low complexity. By supplying a malicious PALETTE COLOR DICOM image containing oversized pixel indices, an attacker can trigger the out-of-bounds read, leaking sensitive heap data embedded in the processed output image while also potentially causing denial of service through application crashes due to memory corruption.
For mitigation details, refer to advisories including CERT/CC vulnerability note VU#536588 at https://kb.cert.org/vuls/id/536588, the Orthanc server site at https://www.orthanc-server.com/, and https://www.machinespirits.de/.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-20926
Vulnerability Data
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…
more
the decoder to read beyond allocated lookup table memory and expose heap contents in the output image.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Developer testing and evaluation directly finds out-of-bounds read flaws through static analysis, fuzzing, and dynamic bounds checks.
Secure engineering principles require bounds checking and memory-safe constructs that stop out-of-bounds reads from being introduced.
Process isolation confines the effects of an out-of-bounds read to the compromised process.
Input validation rejects malformed indices or lengths that would otherwise cause reads outside buffer bounds.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Vulnerability scanning and recording can discover instances of out-of-bounds reads after code is deployed.
Routine patching replaces vulnerable code containing out-of-bounds read flaws.
Secure-development practices such as bounds checking and memory-safe languages directly prevent out-of-bounds reads.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Logging can record evidence of an out-of-bounds read but does not prevent the weakness itself.
Secure development life cycle mandates input validation and bounds checking that directly prevent out-of-bounds reads.
Application security requirements include explicit bounds and memory-safety specifications that mitigate buffer over-reads.
Secure system architecture and engineering principles require memory-safe design patterns and runtime protections against out-of-bounds access.
Secure coding standards explicitly forbid unsafe pointer arithmetic and mandate bounds-checked reads, eliminating CWE-125.
Security testing in development and acceptance includes fuzzing and static analysis that detect out-of-bounds read defects before release.