Forensics Bugs (#1 recoverjpeg)

recoverjpeg

    const char *buffer = file_name(dir_format, file_format, begin_index + i);
      i++;
      if (verbose) {
        printf("%s %ld bytes\n", buffer, (long) size);
      }
      fdout = open(buffer, O_WRONLY | O_CREAT, 0666);
      if (fdout < 0) {
        fprintf(stderr, "Unable to open %s for writing\n", buffer);
        exit(1);
      }

 ...

Writes to an output file (e.g., image00000.jpg) and doesn't check for it being a symlink - hence an attacker could create a symlink pointing to a privileged file that the person running recoverjpeg has write access to. This is mitigated in /tmp /var/tmp by the Linux kernel, but it's still a bug.

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