dbcve.org
Actively exploited in the wild. This CVE is on the CISA Known Exploited Vulnerabilities list — treat remediation as urgent. Federal remediation due by 23 Oct 2025.
BashApplication · Gnu

CVE-2014-6278

HIGH · 8.8 CVSS v3.1 Published 2014-09-30
Patch available
A vendor patch is available. No clean upgrade release — apply the published patch.
See remediation →
100/100
Remediation priority · Urgent
In the wild High EPSS Public exploit Remotely reachable No privileges Patch available

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

This is an incomplete fix for the original Shellshock vulnerabilities (CVE-2014-6271, CVE-2014-7169, CVE-2014-6277). GNU Bash through version 4.3 bash43-026 fails to properly parse function definitions embedded within environment variable values, allowing remote attackers to execute arbitrary commands by setting crafted environment variables. Attack vectors include OpenSSH ForceCommand, Apache mod_cgi/mod_cgid modules, and DHCP client scripts where environment variables are set across privilege boundaries.

MitigationUpgrade Bash to a version newer than bash43-026 that contains the complete fix, or apply vendor-specific patches for this incomplete fix. Audit systems using Bash in privilege boundary contexts (SSH, CGI, DHCP clients) for exposure.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
BashApplication
Affected:= 1.14.0= 1.14.1= 1.14.2= 1.14.3= 1.14.4= 1.14.5= 1.14.6= 1.14.7= 2.0= 2.01= 2.01.1= 2.02

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check installed Bash version
    Run `bash --version` and note the version number displayed
    Affected if The version is 1.14.0 through 1.14.7, 2.0, 2.01, 2.01.1, or 2.02
  2. Test for function definition parsing vulnerability
    Run `env X='() { :;}; echo vulnerable' bash -c "echo test"` and observe output
    Affected if The word 'vulnerable' appears in the output, indicating arbitrary command execution occurred
  3. Verify vulnerable context: OpenSSH ForceCommand
    Check SSH configuration in /etc/ssh/sshd_config for 'ForceCommand' directive or examine any scripts using 'ForceCommand'
    Affected if ForceCommand is configured and the system uses Bash as the shell
  4. Verify vulnerable context: Apache mod_cgi
    Check Apache configuration for 'mod_cgi' module enabled and any ScriptAlias or Script directives using CGI scripts that invoke Bash
    Affected if mod_cgi is enabled and CGI scripts execute using Bash
  5. Verify vulnerable context: DHCP client
    Examine /etc/dhcp/dhclient-enter-hooks.d/ or check if the DHCP client script invokes Bash
    Affected if DHCP client scripts are configured to run Bash hooks

A system is affected if Bash version is within the listed range AND the vulnerability test outputs 'vulnerable' AND the system exposes Bash through privileged contexts like SSH ForceCommand, Apache CGI, or DHCP clients.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Patch available Apply the vendor patch
Vendor patch lcamtuf.blogspot.com →
Interim mitigation

Upgrade Bash to a version newer than bash43-026 that contains the complete fix, or apply vendor-specific patches for this incomplete fix. Audit systems using Bash in privilege boundary contexts (SSH, CGI, DHCP clients) for exposure.

Recommended fix High confidence

Bash 4.3 patch 28 or later (bash-4.3-028 and above)

  1. 1. Identify the current Bash version by running: bash --version
  2. 2. Check your distribution's package manager for available updates (e.g., yum check-update or apt-get update)
  3. 3. Apply the security update: On RHEL/CentOS/Fedora run: yum update bash On Debian/Ubuntu run: apt-get update && apt-get install bash
  4. 4. Verify the updated version includes the fix by checking: env x='() { :;}; echo vulnerable' bash -c "echo this is a test"
  5. 5. If the command outputs 'vulnerable', the patch is not applied; if it outputs 'this is a test', the system is fixed
Caveat Minimal risk; Bash patch updates are backward compatible. In rare cases, custom shell scripts relying on specific parsing edge cases may need adjustment.

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Bash Exploited in the wild — priority engagement
  • Consultation3.0 h
  • Implementation6.0 h
  • Testing4.0 h
  • Review / QA2.0 h
15.0 hours of engineering $2,640
Get it fixed fast

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,224.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2014-6278 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2014-6278 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data