alpine 3.7
format weakness #5

4

Weakness Breakdown


Definition:

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, and note that sprintf variations do not always 0-terminate.

File Name:

cabal/src/zlib-0.6.1.2/cbits/gzguts.h

Context:

The highlighted line of code below is the trigger point of this particular Alpine 3.7 format weakness.

 #  ifndef HAVE_VSNPRINTF
#    define HAVE_VSNPRINTF
#  endif
#endif

#if defined(MSDOS) && defined(__BORLANDC__) && (BORLANDC > 0x410)
#  ifndef HAVE_VSNPRINTF
#    define HAVE_VSNPRINTF
#  endif
#endif

#ifndef HAVE_VSNPRINTF
#  ifdef MSDOS
/* vsnprintf may exist on some MS-DOS compilers (DJGPP?),
   but for now we just assume it doesn't. */
#    define NO_vsnprintf
#  endif
#  ifdef __TURBOC__
#    define NO_vsnprintf
#  endif
#  ifdef WIN32
/* In Win32, vsnprintf is available as the "non-ANSI" _vsnprintf. */
#    if !defined(vsnprintf) && !defined(NO_vsnprintf)
#      if !defined(_MSC_VER) || ( defined(_MSC_VER) && _MSC_VER < 1500 )
#         define vsnprintf _vsnprintf
#      endif
#    endif
#  endif
#  ifdef __SASC
#    define NO_vsnprintf
#  endif
#  ifdef VMS
#    define NO_vsnprintf
#  endif
#  ifdef __OS400__
#    define NO_vsnprintf
#  endif
#  ifdef __MVS__
#    define NO_vsnprintf
#  endif
#endif

/* unlike snprintf (which is required in C99, yet still not supported by
   Microsoft more than a decade later!), _snprintf does not guarantee null
   termination of the result -- however this is only used in gzlib.c where
   the result is assured to fit in the space provided */
#ifdef _MSC_VER
#  define snprintf _snprintf
#endif
 

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