CVE-2026-119618 Apache HTTP Server remote code execution vulnerability, Digi Mart USA News: A critical synchronization vulnerability, tracked as CVE-2026-119618, has been identified in the HTTP/2 module (mod_http2) of Apache HTTP Server. The flaw stems from a concurrent execution race condition within the assign_headers() function when handling shared resources.
If successfully exploited, a remote, unauthenticated attacker can corrupt heap memory to achieve arbitrary code execution. As of the time of the publisher’s blog post, no exploit is available and there are no reports of exploitation in the wild.
The vulnerability was independently discovered by Anthropic and Google Cloud’s Vulnerability Research Team. Due to improper synchronization when executing concurrent threads that share resources, an attacker can trigger heap corruption.
This memory corruption can ultimately be leveraged to execute arbitrary commands with the privileges of the web server process.
The publisher notes that in cloud environments, a compromised Apache instance running containerized or virtualized workloads can serve as an entry point for lateral movement, potentially exposing adjacent microservices or cloud metadata endpoints. According to Wiz data, 64% of cloud environments have resources vulnerable to CVE-2026-119618, and 51% of cloud environments have publicly exposed instances.
The publisher notes this does not take configuration into account.
Security teams are advised to upgrade affected installations to Apache HTTP Server version 2.4.71 or later, which addresses the race condition in assign_headers(). Teams managing standalone mod_h2 builds from GitHub should upgrade the module to a version newer than 2.0.42.
If immediate patching is not possible, the publisher recommends temporarily disabling HTTP/2 support to eliminate the attack vector by restricting active protocols to HTTP/1.1, removing h2 and h2c references in the configuration file such as httpd.conf.
