alpine 3.8
format weakness #4


Weakness Breakdown


A format string exploit occurs when the data of an input string is evaluated as a command by the program. This class of attacks is very similar to buffer overflows since an attacker could execute code, read the stack or cause new behaviors that compromise security. Learn more about format string attacks on OWASP attack index.

Warning code(s):

If format strings can be influenced by an attacker, they can be exploited.

File Name:



The highlighted line of code below is the trigger point of this particular Alpine 3.8 format weakness.

 # endif

#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
#   define vfprintf rpl_vfprintf
#  endif
#  define GNULIB_overrides_vfprintf 1
_GL_FUNCDECL_RPL (vfprintf, int, (FILE *fp, const char *format, va_list args)
                                 _GL_ATTRIBUTE_FORMAT_PRINTF (2, 0)
                                 _GL_ARG_NONNULL ((1, 2)));
#  else
_GL_FUNCDECL_RPL (vfprintf, int, (FILE *fp, const char *format, va_list args)
                                 _GL_ATTRIBUTE_FORMAT_PRINTF_SYSTEM (2, 0)
                                 _GL_ARG_NONNULL ((1, 2)));
#  endif
_GL_CXXALIAS_RPL (vfprintf, int, (FILE *fp, const char *format, va_list args));
# else
/* Need to cast, because on Solaris, the third parameter is
                                                      __va_list args
   and GCC's fixincludes did not change this to __gnuc_va_list.  */
_GL_CXXALIAS_SYS_CAST (vfprintf, int,
                       (FILE *fp, const char *format, va_list args));
# endif
_GL_CXXALIASWARN (vfprintf);
# if !GNULIB_overrides_vfprintf
#  undef vfprintf
# endif
/* Assume vfprintf is always declared.  */
_GL_WARN_ON_USE (vfprintf, "vfprintf is not always POSIX compliant - "
                 "use gnulib module vfprintf-posix for portable "
                      "POSIX compliance");

#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
#   undef vfscanf
#   define vfscanf rpl_vfscanf
#  endif
_GL_FUNCDECL_RPL (vfscanf, int,
                  (FILE *stream, const char *format, va_list args)
                  _GL_ATTRIBUTE_FORMAT_SCANF_SYSTEM (2, 0)
                  _GL_ARG_NONNULL ((1, 2)));
_GL_CXXALIAS_RPL (vfscanf, int, 

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