Critical remote code execution flaw in Apache HTTP Server

A critical security flaw has been disclosed for servers running Apache HTTP Server. According to the report, the issue tracked as CVE-2026-119618 sits in mod_http2, the module that provides HTTP/2 support. It stems from a race condition that appears when header data is handled concurrently across shared resources, which can corrupt heap memory.

That memory corruption can go as far as letting a remote, unauthenticated attacker execute arbitrary code on the server. In practice, someone could run commands with the privileges of the web server process. The article says the flaw was found independently by Anthropic and Google Cloud's vulnerability research team. At the time of publication, there was no known exploit and no reports of it being used in the wild.

The bigger worry is cloud environments. According to the report, Wiz data shows 64% of cloud environments have resources vulnerable to CVE-2026-119618, and 51% have publicly exposed instances. A compromised Apache instance running containerized or virtualized workloads can become an entry point for lateral movement, potentially exposing nearby microservices or cloud metadata endpoints.

The article's first recommendation is to upgrade Apache HTTP Server to version 2.4.71 or later. For standalone mod_h2 builds managed from GitHub, the module should be moved to a version newer than 2.0.42. If patching is not possible right away, temporarily disabling HTTP/2 by removing the h2 and h2c references from the configuration file is suggested to close off the attack path.