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CVE-2014-7187: GNU Bash: Denial of service

CVE-2014-7187 has a CVSS v2 base score of 10.0 (the maximum on that scale) and affects GNU Bash. Per its scoring, it can be exploited over the network, without authentication. The scored impact on confidentiality, integrity and availability is the highest available.

Vulnerability description

Off-by-one error in the read_token_word function in parse.y in GNU Bash through 4.3 bash43-026 allows remote attackers to cause a denial of service (out-of-bounds array access and application crash) or possibly have unspecified other impact via deeply nested for loops, aka the "word_lineno" issue.

Severity breakdown

CVSS v2.0 10.0: AV:N/AC:L/Au:N/C:C/I:C/A:C

Access vector: Network. Exploitable remotely over the network.
Access complexity: Low. No special conditions are required.
Authentication: None. No authentication is needed.
Confidentiality impact: Complete. Total information disclosure.
Integrity impact: Complete. Total loss of integrity.
Availability impact: Complete. Total shutdown of the component.

Underlying weakness

CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary.

Affected products

GNU Bash: 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