CVE-2026-40076
HIGHOpenMRS Core is an open source electronic medical record system platform. In versions 2.7.8 and earlier and versions 2.8.0 through 2.8.5, the module upload endpoint at POST `/openmrs/ws/rest/v1/module`…
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Description
OpenMRS Core is an open source electronic medical record system platform. In versions 2.7.8 and earlier and versions 2.8.0 through 2.8.5, the module upload endpoint at POST /openmrs/ws/rest/v1/module is vulnerable to a Zip Slip path traversal attack. During automatic extraction of uploaded .omod archives in WebModuleUtil.startModule(), ZIP entries under web/module/ are checked only to see whether the full entry path starts with .., and the remaining path is then concatenated into the destination path without normalization or a boundary check. A crafted archive can therefore include entries such as web/module/../../../../malicious.jsp and cause files to be written outside the intended module directory.
An authenticated attacker with module upload access can write arbitrary files to locations such as the web application root and achieve remote code execution by uploading a JSP file and then requesting it. The issue is compounded by the fact that the module.allow_web_admin runtime property is enforced in the legacy UI controller but not in the REST API upload path, so deployments relying on that property to block web-based module administration remain exposed through the REST endpoint. This issue has been fixed in versions after 2.7.8 in the 2.7.x line and in version 2.8.6 and later.
Affected Products
openmrsopenmrsDetection & mitigation playbook
Vendor / applianceDetect
Inventory every openmrs openmrs deployment and check each version against the affected-products list above. Because the exploit targets the running system rather than your application code, also watch for remote code execution at the network and runtime layer — O3 flags the exploit behaviour from runtime telemetry and egress traffic even before a vulnerable build is confirmed.
Remediation status
No patch has shipped for CVE-2026-40076 yet — track the openmrs openmrs advisory for a fixed release and apply the workarounds below in the meantime.
Mitigate without a patch
Cut exposure now: restrict the management/admin interface to trusted networks, segment the device, and apply the vendor's recommended configuration mitigations and any WAF/IPS signature. O3's runtime protection blocks the exploit chain at execution, holding the line on unpatched or end-of-life systems until you can patch.
How O3 protects you
O3 detects and blocks CVE-2026-40076 exploitation at runtime: eBPF exploit-chain detection, plus L7 egress monitoring that catches the post-exploitation callback and severs the attacker's outbound channel.
Tailored to CVE-2026-40076. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-40076 being exploited in your environment?
O3's eBPF runtime sensors and L7 egress monitoring detect and block the CVE-2026-40076 exploit chain at execution — protecting unpatched and end-of-life systems until the vendor patch is applied.