CVE-2014-6271

CVE-2014-6271 is a critical-severity vulnerability in Debian Debian Linux with a CVSS 3.x base score of 9.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2022-01-28). The underlying weakness is classified as CWE-78.

Key facts

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.

Frequently asked questions

What is CVE-2014-6271?
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.
How severe is CVE-2014-6271?
CVE-2014-6271 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2014-6271 being actively exploited?
Yes. CVE-2014-6271 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2022-01-28, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2014-6271?
CVE-2014-6271 primarily affects Debian Debian Linux. In total, 297 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2014-6271?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2014-6271 have an EU (EUVD) identifier?
Yes. CVE-2014-6271 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2014-6157. It is also flagged as exploited in the EUVD (since 2022-01-28).
When was CVE-2014-6271 published?
CVE-2014-6271 was published on 2014-09-24 and last updated on 2026-06-17.

References

Affected products (297)

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