CVE-2026-5439
7.5 · HIGHOverview
CVE-2026-5439 is a high-severity vulnerability affecting orthanc-server orthanc. It was published on April 9, 2026 and has a CVSS 3.1 base score of 7.5 (HIGH).
This vulnerability has a CVSS 3.1 base score of 7.5, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
A memory exhaustion vulnerability exists in ZIP archive processing. Orthanc automatically extracts ZIP archives uploaded to certain endpoints and trusts metadata fields describing the uncompressed size of archived files. An attacker can craft a small ZIP archive containing a forged size value, causing the server to allocate extremely large buffers during extraction.
Remediation
Check the references section for vendor advisories and patches from orthanc-server. Update orthanc to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| orthanc-server | orthanc | >= 0, < 1.12.11 | Affected |
Frequently Asked Questions
What is CVE-2026-5439?
CVE-2026-5439 is a high-severity vulnerability affecting orthanc-server orthanc. It was published on April 9, 2026 and has a CVSS 3.1 base score of 7.5 (HIGH).
How severe is CVE-2026-5439?
This vulnerability has a CVSS 3.1 base score of 7.5, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-5439?
Check the references section for vendor advisories and patches from orthanc-server. Update orthanc to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-5439?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-5439 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
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