CVE-2014-6277

CVE-2014-6277 is a critical-severity vulnerability in Gnu Bash with a CVSS 2.0 base score of 10.0. Its EPSS exploit-prediction score of 64% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-78.

Key facts

Description

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 code or cause a denial of service (uninitialized memory access, and untrusted-pointer read and write operations) 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 and CVE-2014-7169.

Frequently asked questions

What is CVE-2014-6277?
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 code or cause a denial of service (uninitialized memory access, and untrusted-pointer read and write operations) 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 and CVE-2014-7169.
How severe is CVE-2014-6277?
CVE-2014-6277 has a CVSS 2.0 base score of 10.0, rated critical severity.
Is CVE-2014-6277 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 64% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2014-6277?
CVE-2014-6277 primarily affects Gnu Bash. In total, 28 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2014-6277?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2014-6277 published?
CVE-2014-6277 was published on 2014-09-27 and last updated on 2026-06-17.

References

Affected products (28)

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