ZDI-26-578: NGINX HTTP Dav Module Alias Directive Integer Underflow Remote Code Execution Vulnerability
An unauthenticated integer underflow (CVE-2026-27654, CVSS 8.1) in NGINX's HTTP Dav module alias directive enables remote code execution.
ZDI advisory ZDI-26-578 describes an integer underflow in the alias directive of the NGINX HTTP Dav module that allows remote attackers to execute arbitrary code. Authentication is not required to exploit the vulnerability. ZDI rated the issue 8.1 on CVSS and assigned CVE-2026-27654.
GeoNetwork Fixes Unauthenticated RCE Chain Affecting Government Geoportal Backends
GeoNetwork patched two chained flaws (CVE-2026-63219, CVE-2026-58400) enabling unauthenticated RCE in government geospatial metadata catalogs.
Two flaws in the open-source GeoNetwork catalog chain into unauthenticated RCE: a missing authorization check on the formatter upload endpoint (CVE-2026-63219, CVSS 8.6) and an unsafe Saxon XSLT processor configuration allowing Java execution (CVE-2026-58400, CVSS 9.1). Fixes shipped in versions 4.4.12 and 4.2.17 on July 8, 2026, with details published August 31. Ethiack fingerprinted 121 internet-exposed vulnerable deployments across 39 countries, 89% tied to government or military agencies. No exploitation in the wild or KEV listing was reported at disclosure.