CVE-2014-7187

Description

An off-by-one error was discovered in the way Bash was handling deeply nested flow control constructs. Depending on the layout of the .bss segment, this could allow arbitrary execution of code that would not otherwise be executed by Bash.

Statement

Red Hat Product Security does not consider this bug to have any security impact on the bash packages shipped in Red Hat Enterprise Linux. A fix for this issue was applied as a hardening in RHSA-2014:1306, RHSA-2014:1311, and RHSA-2014:1312.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

CVSS v2 Score Breakdown

Red HatNVDcve.org
Base Score4.610N/A
Attack VectorLocalNetworkN/A
Access ComplexityLowLowN/A
AuthenticationNoneNoneN/A
Confidentiality ImpactPartialCompleteN/A
Integrity ImpactPartialCompleteN/A
Availability ImpactPartialCompleteN/A

Vector

Red Hat: AV:L/AC:L/Au:N/C:P/I:P/A:P

NVD: AV:N/AC:L/Au:N/C:C/I:C/A:C

Understanding the Weakness (CWE)

Availability

Technical Impact: DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Instability

This weakness will generally lead to undefined behavior and therefore crashes. In the case of overflows involving loop index variables, the likelihood of infinite loops is also high.

Integrity

Technical Impact: Modify Memory

If the value in question is important to data (as opposed to flow), simple data corruption has occurred. Also, if the wrap around results in other conditions such as buffer overflows, further memory corruption may occur.

Confidentiality,Availability,Access Control

Technical Impact: Execute Unauthorized Code or Commands; Bypass Protection Mechanism

This weakness can sometimes trigger buffer overflows which can be used to execute arbitrary code. This is usually outside the scope of a program's implicit security policy.

Acknowledgements

This issue was discovered by Florian Weimer (Red Hat Product Security).

Frequently Asked Questions

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