Description

The product does not check for an error after calling a function that can return with a NULL pointer if the function fails, which leads to a resultant NULL pointer dereference.

While unchecked return value weaknesses are not limited to returns of NULL pointers (see the examples in CWE-252), functions often return NULL to indicate an error status. When this error condition is not checked, a NULL pointer dereference can occur.

Modes of Introduction:

– Implementation

Likelihood of Exploit:

Related Weaknesses

CWE-252
CWE-476

Consequences

Availability: DoS: Crash, Exit, or Restart

Integrity, Confidentiality, Availability: Execute Unauthorized Code or Commands, Read Memory, Modify Memory

In rare circumstances, when NULL is equivalent to the 0x0 memory address and privileged code can access it, then writing or reading memory is possible, which may lead to code execution.

Potential Mitigations

CVE References

• CVE-2008-1052
  • Large Content-Length value leads to NULL pointer dereference when malloc fails.

• CVE-2006-6227
  • Large message length field leads to NULL pointer dereference when malloc fails.

• CVE-2006-2555
  • Parsing routine encounters NULL dereference when input is missing a colon separator.

• CVE-2003-1054
  • URI parsing API sets argument to NULL when a parsing failure occurs, such as when the Referer header is missing a hostname, leading to NULL dereference.

• CVE-2008-5183
  • chain: unchecked return value can lead to NULL dereference