CVE-2026-5443 | Heap Buffer Overflow in DICOM Image Decoder (Palette Color Decode)

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.

Published: 2026-04-09 Last update: 2026-04-14 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-5443 is rated Moderate Risk (46/100): CVSS Critical severity, with low exploitation likelihood (EPSS 0.06%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-5443

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-04-15 0.02% 0.06% +0.04%
2 2026-04-10 0.02%

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-5443

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 5.9 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2026-5443

OS Trackers for CVE-2026-5443

vendor priority summary link
debian not yet assigned CVE-2026-5443 not yet assigned priority: Debian including 1 source packages (orthanc), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 3, resolved 2. https://security-tracker.debian.org/tracker/CVE-2026-5443
ubuntu medium CVE-2026-5443 medium priority: Ubuntu including 1 source packages (orthanc), 8 status rows across 8 suites (bionic, focal, jammy, noble, questing, resolute, upstream, xenial): needs-triage 8. https://ubuntu.com/security/CVE-2026-5443

Affected software / configurations for CVE-2026-5443

Vendor Product Version Raw CPE
orthanc-server orthanc < 1.12.11 cpe:2.3:a:orthanc-server:orthanc:*:*:*:*:*:*:*:*

References for CVE-2026-5443

URL Tags
https://kb.cert.org/vuls/id/536588 Third Party Advisory VDB Entry
https://www.machinespirits.de/ Not Applicable
https://www.orthanc-server.com/ Product
cvelogic Threat Intelligence