CVE-2026-40076

CriticalPublic PoC

Published: 06 May 2026

Published

06 May 2026

Modified

11 May 2026

KEV Added

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Patch

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CVSS Score v4 9.4 CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS Score 0.0085 53.7th percentile

Risk Priority 70 floored blend · peak EPSS

Summary

CVE-2026-40076 is a critical-severity Path Traversal (CWE-22) vulnerability in Openmrs Openmrs. Its CVSS base score is 9.4 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 46.3% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

OWASP Top 10 for Web (2025)

EU & UK References

🇪🇺 ENISA EUVD: EUVD-2026-28151

Vulnerability details

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.

CWE(s): CWE-22

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access

Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.

attack.mitre.org →

T1505.003 Web Shell Persistence

Adversaries may backdoor web servers with web shells to establish persistent access to systems.

attack.mitre.org →

Why these techniques?

Zip Slip in authenticated module upload endpoint enables arbitrary file write to web root for JSP-based RCE (T1190 initial exploitation of public-facing app; T1100 web shell deployment).

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0