BADFUNC.TTYNAME : Use of ttyname

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CodeSonar^® 9.2p0

CONFIDENTIAL

CodeSecure Inc

C and C++

Binaries

BADFUNC.TTYNAME : Use of ttyname

Summary

A use of ttyname(), which may return a non-null-terminated string depending on the implementation, and is not required to be thread-safe.

Properties

Class Name

Use of ttyname

Significance

security

Mnemonic

BADFUNC.TTYNAME

Categories

CWE	CWE:676	Use of Potentially Dangerous Function
CERT-C	CERT-C:CON33-C	Avoid race conditions when using library functions
BSI	BSI:TTYNAME	Use of ttyname
OWASP-2021	OWASP-2021:A4	Insecure design
OWASP-2025	OWASP-2025:A06	Insecure Design

Availability

Available for C and C++.

Enabling

Checks for this warning class are disabled by default. To enable them, add the following WARNING_FILTER rule to the project configuration file.

WARNING_FILTER += allow class="Use of ttyname"

To enable all BSI-related classes, including all BSI-specific BADFUNC classes, use the bsi configuration preset.

Resolution

If thread-safety is required, do not use ttyname().

When you see a Use of ttyname warning, make sure that subsequent uses of the return value take into account the possibility that it is not null-terminated. If so, you can change the warning state to Suppressed.

Relevant Configuration File Parameters

This class is implemented using a BAD_FUNCTION_* rule set in the general template configuration file.

To include an additional function or set of functions in the checks for this class, create a new set of BAD_FUNCTION_* rules in which the BAD_FUNCTION_REGEX setting matches the function or set of functions you want to check and the remaining rules match those in the other sets for this class.
To remove a function or set of functions from the checks for this class, edit the configuration file to comment out the corresponding set of BAD_FUNCTION_* rules.

The following configuration file parameters affect checks for this warning class.

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