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CVE-2014-7169: GNU Bourne-Again Shell (Bash) Arbitrary Code Execution Vulnerability

CVE-2014-7169 is rated critical with a CVSS v3.1 base score of 9.8 and affects GNU Bourne-Again Shell (Bash), along with 73 other products in NVD’s configuration data. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available. CISA added it to its Known Exploited Vulnerabilities catalog on 2022-01-28, which means exploitation in the wild has been observed.

Vulnerability description

GNU Bash through 4.3 bash43-025 processes trailing strings after certain malformed function definitions in the values of environment variables, which allows remote attackers to write to files or possibly have unknown other impact 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.

Severity breakdown

CVSS v3.1 9.8: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
Attack complexity: Low. No special conditions; the attack can be repeated reliably.
Privileges required: None. No account or prior access is needed.
User interaction: None. No action from any user is needed.
Scope: Unchanged. Impact stays within the vulnerable component.
Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
Availability impact: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-78: Improper Neutralization of Special Elements used in an OS Command

The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command before it is sent to a downstream component.

Affected products

GNU Bash: up to and including 4.3
Arista Eos: from 4.9.0 before 4.9.12; from 4.10.0 before 4.10.9; from 4.11.0 before 4.11.11; from 4.12.0 before 4.12.9; from 4.13.0 before 4.13.9; from 4.14.0 before 4.14.4f
Oracle Linux: 4; 5; 6
QNAP Qts: before 4.1.1; 4.1.1; 4.1.1 build_0927
Mageia: 3.0; 4.0
Red Hat Gluster Storage Server For On Premise: 2.1
Red Hat Virtualization: 3.4
Red Hat Enterprise Linux: 4.0; 5.0; 6.0; 7.0
Red Hat Enterprise Linux Desktop: 5.0; 6.0; 7.0
Red Hat Enterprise Linux Eus: 5.9; 6.4; 6.5; 7.3; 7.4; 7.5; 7.6; 7.7
Red Hat Enterprise Linux For IBM Z Systems: 5.9_s390x; 6.4_s390x; 6.5_s390x; 7.3_s390x; 7.4_s390x; 7.5_s390x; 7.6_s390x; 7.7_s390x
Red Hat Enterprise Linux For Power Big Endian: 5.0_ppc; 5.9_ppc; 6.0_ppc64; 6.4_ppc64; 7.0_ppc64
Red Hat Enterprise Linux For Power Big Endian Eus: 6.5_ppc64; 7.3_ppc64; 7.4_ppc64; 7.5_ppc64; 7.6_ppc64; 7.7_ppc64
Red Hat Enterprise Linux For Scientific Computing: 6.0; 7.0
Red Hat Enterprise Linux Server: 5.0; 6.0; 7.0