https://ahm4ddm.github.io/tags/ret2libc/ Recent content in Ret2libc on ~/.ahm4ddm Hugo en Sun, 07 Feb 2021 00:38:53 +0700 https://ahm4ddm.github.io/writeups/asis2017-mrs.hudson/ Sun, 07 Feb 2021 00:38:53 +0700 https://ahm4ddm.github.io/writeups/asis2017-mrs.hudson/ <p><a href="https://github.com/ahm4ddm/larebinex/blob/main/64/mrs._hudson/mrs._hudson">klik disini</a> untuk download file.</p> <p>Kita cek identitas dari file.</p> <div class="highlight"><div style="color:#f8f8f2;background-color:#272822;-moz-tab-size:4;-o-tab-size:4;tab-size:4;-webkit-text-size-adjust:none;"> <table style="border-spacing:0;padding:0;margin:0;border:0;"><tr><td style="vertical-align:top;padding:0;margin:0;border:0;"> <pre tabindex="0" style="color:#f8f8f2;background-color:#272822;-moz-tab-size:4;-o-tab-size:4;tab-size:4;-webkit-text-size-adjust:none;"><code><span style="white-space:pre;-webkit-user-select:none;user-select:none;margin-right:0.4em;padding:0 0.4em 0 0.4em;color:#7f7f7f">1 </span><span style="white-space:pre;-webkit-user-select:none;user-select:none;margin-right:0.4em;padding:0 0.4em 0 0.4em;color:#7f7f7f">2 </span></code></pre></td> <td style="vertical-align:top;padding:0;margin:0;border:0;;width:100%"> <pre tabindex="0" style="color:#f8f8f2;background-color:#272822;-moz-tab-size:4;-o-tab-size:4;tab-size:4;-webkit-text-size-adjust:none;"><code class="language-fallback" data-lang="fallback"><span style="display:flex;"><span>$file mrs._hudson </span></span><span style="display:flex;"><span>mrs._hudson: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, for GNU/Linux 2.6.32, BuildID[sha1]=a99b54f5a0f90ebade826e34188ac1f5eebb2cc7, not stripped </span></span></code></pre></td></tr></table> </div> </div><p>Didapatkan file ELF, 64bit, not stripped, dynamically linked.<br> Selanjutnya kita cek proteksi pada file tersebut.</p> <div class="highlight"><div style="color:#f8f8f2;background-color:#272822;-moz-tab-size:4;-o-tab-size:4;tab-size:4;-webkit-text-size-adjust:none;"> <table style="border-spacing:0;padding:0;margin:0;border:0;"><tr><td style="vertical-align:top;padding:0;margin:0;border:0;"> <pre tabindex="0" style="color:#f8f8f2;background-color:#272822;-moz-tab-size:4;-o-tab-size:4;tab-size:4;-webkit-text-size-adjust:none;"><code><span style="white-space:pre;-webkit-user-select:none;user-select:none;margin-right:0.4em;padding:0 0.4em 0 0.4em;color:#7f7f7f">1 </span><span style="white-space:pre;-webkit-user-select:none;user-select:none;margin-right:0.4em;padding:0 0.4em 0 0.4em;color:#7f7f7f">2 </span><span style="white-space:pre;-webkit-user-select:none;user-select:none;margin-right:0.4em;padding:0 0.4em 0 0.4em;color:#7f7f7f">3 </span><span style="white-space:pre;-webkit-user-select:none;user-select:none;margin-right:0.4em;padding:0 0.4em 0 0.4em;color:#7f7f7f">4 </span><span style="white-space:pre;-webkit-user-select:none;user-select:none;margin-right:0.4em;padding:0 0.4em 0 0.4em;color:#7f7f7f">5 </span><span style="white-space:pre;-webkit-user-select:none;user-select:none;margin-right:0.4em;padding:0 0.4em 0 0.4em;color:#7f7f7f">6 </span><span style="white-space:pre;-webkit-user-select:none;user-select:none;margin-right:0.4em;padding:0 0.4em 0 0.4em;color:#7f7f7f">7 </span></code></pre></td> <td style="vertical-align:top;padding:0;margin:0;border:0;;width:100%"> <pre tabindex="0" style="color:#f8f8f2;background-color:#272822;-moz-tab-size:4;-o-tab-size:4;tab-size:4;-webkit-text-size-adjust:none;"><code class="language-fallback" data-lang="fallback"><span style="display:flex;"><span>$checksec mrs._hudson </span></span><span style="display:flex;"><span> Arch: amd64-64-little </span></span><span style="display:flex;"><span> RELRO: Partial RELRO </span></span><span style="display:flex;"><span> Stack: No canary found </span></span><span style="display:flex;"><span> NX: NX disabled </span></span><span style="display:flex;"><span> PIE: No PIE (0x400000) </span></span><span style="display:flex;"><span> RWX: Has RWX segments </span></span></code></pre></td></tr></table> </div> </div><p>Kita lihat di GDB didapatkan:</p>