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CVE-2014-6271

GNU Bourne-Again Shell (Bash) Arbitrary Code Execution Vulnerability

  • Critical 9.8
  • Exploited: added to CISA KEV 28 Jan 2022
  • A public exploit reference is listed

Description

GNU Bash through 4.3 processes trailing strings after function definitions in the values of environment variables, which allows remote attackers to execute arbitrary code 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, aka "ShellShock." NOTE: the original fix for this issue was incorrect; CVE-2014-7169 has been assigned to cover the vulnerability that is still present after the incorrect fix.

Key facts

Published
24 Sep 2014
Last changed
22 Oct 2025
Assigned by
debian
KEV added
28 Jan 2022
KEV fix due
28 Jul 2022
EPSS
99.999% likely to be exploited in the next 30 days, higher than 99.993% of CVEs (scores for 15 Nov 2026)
SSVC (CISA)
Exploitation: active; Automatable: yes; Technical impact: total

Severity scores

Each score is shown as its source gave it. They are not averaged or merged.

  • 9.8CVSS 3.1, Criticalfrom CISA (ADP container)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

What to do

  • Apply updates per vendor instructions.CISA KEV required action

Historical context and remediation

This reference retains the original CVE publication date. A recent record update does not mean a new attack occurred.

No separately sourced impact summary is available on this page yet. Consult the description, version data and dated exploitation evidence.

Version statuses below come from the CNA. An “unaffected” version is not necessarily a currently supported release or proof of a patch date. EPSS is a dated risk estimate, not a count of historical attacks.

Read the original CVE record.

Affected products

VendorProductVersions
n/an/a
  • n/a (affected)

Timeline

  1. 24 Sep 2014 Published
  2. 28 Jan 2022 CVE-2014-6271 added to CISA KEV
  3. 28 Jan 2022 Added to the CISA KEV catalogue

Weakness

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References