Alternative functions that limit the number of bytes copied are often recommended to mitigate buffer overflow vulnerabilities. For example
strncpy()instead ofstrcpy()strncat()instead ofstrcat()fgets()instead ofgets()snprintf()instead ofsprintf()
These functions truncate strings that exceed the specified limits. Additionally, some functions such as strncpy() do not guarantee that the resulting string is null terminated [[STR32-C. Null terminate byte strings as required]].
Unintentional truncation results in a loss of data and, in some cases, leads to software vulnerabilities.
Unable to render {include} The included page could not be found.
Unable to render {include} The included page could not be found.
Unable to render {include} The included page could not be found.
Exceptions
STR03-EX1: The intent of the programmer is to intentionally truncate the null-terminated byte string.
Risk Assessment
Truncating strings can lead to a loss of data.
Recommendation |
Severity |
Likelihood |
Remediation Cost |
Priority |
Level |
|---|---|---|---|---|---|
STR03-A |
1 (low) |
1 (unlikely) |
2 (medium) |
P2 |
L3 |
Automated Detection
The LDRA tool suite V 7.6.0 is able to detect violations of this recommendation.
Fortify SCA Version 5.0 with CERT C Rule Pack can detect violations of this recommendation.
Related Vulnerabilities
Search for vulnerabilities resulting from the violation of this rule on the CERT website.
References
[[ISO/IEC 9899-1999]] Section 7.21, "String handling <string.h>"
[[Seacord 05a]] Chapter 2, "Strings"
[[ISO/IEC TR 24731-1-2007]]
STR02-A. Sanitize data passed to complex subsystems 07. Characters and Strings (STR) STR05-A. Prefer making string literals const-qualified