---
id: "CVE-2018-11776"
kind: "vulnerability"
aliases: ["CVE-2018-11776"]
title: "Apache Struts: Apache Struts Remote Code Execution Vulnerability"
severity: "critical"
cvss: 9.3
epss: 0.99994
exploited: true
status: "open"
category: "runtime"
products: [{"name": "Apache Struts", "fixed": [], "affected": "", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["apache-struts", "exploited", "java", "runtime", "self-hosted"]
not_affected_if: ["default-config", "no-alwaysselectfullnamespace"]
published_at: "2018-08-22T13:29:00+00:00"
first_seen_at: "2026-10-23T19:11:53+00:00"
updated_at: "2026-10-23T21:57:35+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2018-11776", "first_seen_at": "2026-10-23T19:11:53+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2018-11776", "first_seen_at": "2026-10-23T19:13:44+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2018-11776", "first_seen_at": "2026-10-23T21:57:35+00:00"}]
---

# Apache Struts: Apache Struts Remote Code Execution Vulnerability

Apache Struts, a Java web framework, can execute attacker-supplied code on the server when specific namespace or URL tag configurations are used. An unauthenticated remote attacker can run code on the server, which can lead to full takeover.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:Apache Struts affected ? fixed ?

## Fix

Upgrade Apache Struts to a fixed release per vendor instructions; the sources do not name the fixed version.

## Timeline

- 2026-10-23T19:11:53+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2018-11776
- 2026-10-23T19:13:44+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2018-11776
- 2026-10-23T21:57:35+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2018-11776

## From the sources

Apache Struts contains a vulnerability that allows for remote code execution under two circumstances. One, where the alwaysSelectFullNamespace option is true and the value isn't set for a result defined in underlying configurations and in same time, its upper package configuration have no or wildcard namespace.  Or, using URL tag which doesn't have value and action set and in same time, its upper package configuration have no or wildcard namespace.

CISA required action: Apply updates per vendor instructions.

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_