Mitigate Baron SameEdit (CVE-2021-3156) vulnerability

sles 15.1
format weakness #3

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:

snappy-1.1.3/snappy-test.cc

Context:

The highlighted line of code below is the trigger point of this particular Sles 15.1 format weakness.

 
string ReadTestDataFile(const string& base, size_t size_limit) {
  string contents;
  const char* srcdir = getenv("srcdir");  // This is set by Automake.
  string prefix;
  if (srcdir) {
    prefix = string(srcdir) + "/";
  }
  file::GetContents(prefix + "testdata/" + base, &contents, file::Defaults()
      ).CheckSuccess();
  if (size_limit > 0) {
    contents = contents.substr(0, size_limit);
  }
  return contents;
}

string ReadTestDataFile(const string& base) {
  return ReadTestDataFile(base, 0);
}

string StringPrintf(const char* format, ...) {
  char buf[4096];
  va_list ap;
  va_start(ap, format);
  vsnprintf(buf, sizeof(buf), format, ap);
  va_end(ap);
  return buf;
}

bool benchmark_running = false;
int64 benchmark_real_time_us = 0;
int64 benchmark_cpu_time_us = 0;
string *benchmark_label = NULL;
int64 benchmark_bytes_processed = 0;

void ResetBenchmarkTiming() {
  benchmark_real_time_us = 0;
  benchmark_cpu_time_us = 0;
}

#ifdef WIN32
LARGE_INTEGER benchmark_start_real;
FILETIME benchmark_start_cpu;
#else  // WIN32
struct timeval benchmark_start_real;
struct rusage benchmark_start_cpu;
#endif  // WIN32

void StartBenchmarkTiming() {
#ifdef WIN32 

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