This section identifies rules and recommendations related to the functions defined in C99 Section 7.20.4, "Communication with the environment".
Recommendations
ENV00-A. Do not store the pointer to the string returned by getenv()
ENV01-A. Do not make assumptions about the size of an environment variable
ENV02-A. Beware of multiple environment variables with the same name
ENV03-A. Sanitize the environment before invoking external programs
ENV04-A. Do not call system() if you do not need a command processor
Rules
ENV30-C. Do not modify the string returned by getenv()
ENV31-C. Do not rely on an environment pointer following an operation that may invalidate it
ENV32-C. Do not call the exit() function more than once
ENV33-C. Do not call the longjmp function to terminate a call to a function registered by atexit()
Risk Assessment Summary
Recommendation |
Severity |
Likelihood |
Remediation Cost |
Priority |
Level |
|---|---|---|---|---|---|
ENV00-A |
1 (low) |
1 (unlikely) |
2 (medium) |
P2 |
L3 |
ENV01-A |
3 (high) |
3 (unlikely) |
3 (low) |
P27 |
L1 |
ENV02-A |
2 (medium) |
1 (unlikely) |
3 (low) |
P6 |
L2 |
ENV03-A |
2 (medium) |
2 (probable) |
2 (medium) |
P8 |
L2 |
ENV04-A |
3 (high) |
2 (probable) |
2 (medium) |
P12 |
L1 |
Rule |
Severity |
Likelihood |
Remediation Cost |
Priority |
Level |
|---|---|---|---|---|---|
ENV30-C |
1 (low) |
1 (unlikely) |
3 (low) |
P3 |
L3 |
ENV31-C |
1 (low) |
1 (unlikely) |
3 (low) |
P3 |
L3 |
ENV32-C |
1 (low) |
1 (unlikely) |
3 (low) |
P3 |
L3 |
ENV33-C |
1 (low) |
1 (unlikely) |
3 (low) |
P3 |
L3 |
Related Rules and Recommendations
TMP33-C. Temporary files must be removed before the program exits 10. Temporary Files (TMP) ENV00-A. Do not store the pointer to the string returned by getenv()