How severe is CVE-2026-5445?

CVE-2026-5445 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability high.

Is CVE-2026-5445 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (47th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-5445?

CVE-2026-5445 affects Orthanc-server Orthanc. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-5445?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2026-5445 have an EU (EUVD) identifier?

Yes. CVE-2026-5445 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-20926.

When was CVE-2026-5445 published?

CVE-2026-5445 was published on 2026-04-09 and last updated on 2026-06-17.

CVE-2026-5445

CVE-2026-5445 is a critical-severity vulnerability in Orthanc-server Orthanc with a CVSS 3.x base score of 9.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-125.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
EPSS exploit prediction: 1% (47th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-20926
Weakness: CWE-125
Affected product: Orthanc-server Orthanc
Published: 2026-04-09
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2026-5445?: 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.
How severe is CVE-2026-5445?: CVE-2026-5445 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability high.
Is CVE-2026-5445 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (47th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-5445?: CVE-2026-5445 affects Orthanc-server Orthanc. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-5445?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2026-5445 have an EU (EUVD) identifier?: Yes. CVE-2026-5445 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-20926.
When was CVE-2026-5445 published?: CVE-2026-5445 was published on 2026-04-09 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:orthanc-server:orthanc:*:*:*:*:*:*:*:*

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