---
id: "CVE-2014-6278"
kind: "vulnerability"
aliases: ["CVE-2014-6278"]
title: "GNU Bash through 4.3 bash43-026 does not properly parse function definitions in the values of environment variables,\u2026"
severity: "critical"
cvss: 10.0
epss: null
exploited: true
status: "open"
category: "infrastructure"
products: [{"name": "GNU GNU Bash", "fixed": [], "affected": "", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 1.14.0", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 1.14.1", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 1.14.2", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 1.14.3", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 1.14.4", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 1.14.5", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 1.14.6", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 1.14.7", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 2.0", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 2.01", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 2.01.1", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 2.02", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 2.02.1", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 2.03", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 2.04", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 2.05", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 3.0", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 3.0.16", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 3.1", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 3.2", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 3.2.48", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 4.0", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 4.1", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 4.2", "ecosystem": "vendor"}, {"name": "gnu bash", "fixed": [], "affected": "= 4.3", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["bash", "cgi", "exploited", "infrastructure", "linux", "self-hosted", "ssh"]
not_affected_if: ["managed-hosting", "no-bash-on-path"]
published_at: "2014-09-30T10:55:04+00:00"
first_seen_at: "2026-10-23T19:11:51+00:00"
updated_at: "2026-10-23T23:44:51+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2014-6278", "first_seen_at": "2026-10-23T19:11:51+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2014-6278", "first_seen_at": "2026-10-23T23:44:51+00:00"}]
---

# GNU Bash through 4.3 bash43-026 does not properly parse function definitions in the values of environment variables,…

GNU Bash can be made to run arbitrary commands through a crafted environment variable, a flaw known as Shellshock. An attacker who can get a value into a Bash environment can run commands as the account running Bash.

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

## Affected

- vendor:GNU GNU Bash affected ? fixed ?
- vendor:gnu bash affected = 1.14.0 fixed ?
- vendor:gnu bash affected = 1.14.1 fixed ?
- vendor:gnu bash affected = 1.14.2 fixed ?
- vendor:gnu bash affected = 1.14.3 fixed ?
- vendor:gnu bash affected = 1.14.4 fixed ?
- vendor:gnu bash affected = 1.14.5 fixed ?
- vendor:gnu bash affected = 1.14.6 fixed ?
- vendor:gnu bash affected = 1.14.7 fixed ?
- vendor:gnu bash affected = 2.0 fixed ?
- vendor:gnu bash affected = 2.01 fixed ?
- vendor:gnu bash affected = 2.01.1 fixed ?
- vendor:gnu bash affected = 2.02 fixed ?
- vendor:gnu bash affected = 2.02.1 fixed ?
- vendor:gnu bash affected = 2.03 fixed ?
- vendor:gnu bash affected = 2.04 fixed ?
- vendor:gnu bash affected = 2.05 fixed ?
- vendor:gnu bash affected = 3.0 fixed ?
- vendor:gnu bash affected = 3.0.16 fixed ?
- vendor:gnu bash affected = 3.1 fixed ?
- vendor:gnu bash affected = 3.2 fixed ?
- vendor:gnu bash affected = 3.2.48 fixed ?
- vendor:gnu bash affected = 4.0 fixed ?
- vendor:gnu bash affected = 4.1 fixed ?
- vendor:gnu bash affected = 4.2 fixed ?
- vendor:gnu bash affected = 4.3 fixed ?

## How to check

Run: env -i bash -c 'env x="() { :;}; echo vulnerable" bash -c "echo test"' and see if 'vulnerable' prints before 'test'.
See which bash binary is in use: bash --version

## Fix

Upgrade bash to a patched release from your OS vendor and restart services that spawn bash.

## Timeline

- 2026-10-23T19:11:51+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2014-6278
- 2026-10-23T23:44:51+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2014-6278

## From the sources

GNU Bash through 4.3 bash43-026 does not properly parse function definitions in the values of environment variables, which allows remote attackers to execute arbitrary commands via a crafted environment, as demonstrated by vectors involving the ForceCommand feature in OpenSSH sshd, the mod_cgi and mod_cgid modules in the Apache HTTP Server, scripts executed by unspecified DHCP clients, and other situations in which setting the environment occurs across a privilege boundary from Bash execution.  NOTE: this vulnerability exists because of an incomplete fix for CVE-2014-6271, CVE-2014-7169, and CVE-2014-6277.

---

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