Frida Hook初次实战

做攻防世界的CTF题，看到有大佬搞Frida的操作，按照大佬做到试了一下

ill-intentions（Native hook）

攻防世界——ill-intentions

frida,frida-server,objection该安装的都安装好

adb连接上机子

由于没有修改apk包，触发按钮的Intent显示不了，用objection手动开启

1 2	objection -g com.example.hellojni explore android intent launch_activity com.example.application.IsThisTheRealOne

效果如下

挂上大佬hook Native的脚本

//tt.js
//出自https://blog.csdn.net/Palmer9/article/details/122464683
//别问脚本什么意思，frida脚本还不太会写
function main() {
    function getjstring(jstr) {
        return Java.vm.getEnv().getStringUtfChars(jstr, null).readCString();
    }
    Java.perform(function () {
        var so_addr = Module.findBaseAddress("libhello-jni.so");
        var perhapsThis_addr = Module.findExportByName("libhello-jni.so", "Java_com_example_application_IsThisTheRealOne_perhapsThis");
        console.log("perhapsThis_addr", perhapsThis_addr);
        Interceptor.attach(perhapsThis_addr, {
            onEnter: function (args) {
                console.log("perhapsThis_args:[1]", getjstring(args[2]), "\n    [2]", getjstring(args[3]), "\n    [3]", getjstring(args[4]), "\n");
            },
            onLeave: function (retval) {
                console.log("perhapsThis_result:", getjstring(retval));
            },
        });

        Interceptor.attach(Module.findExportByName("libhello-jni.so", "Java_com_example_application_ThisIsTheRealOne_orThat"), {
            onEnter: function (args) {
                console.log("orThat_args:[1]", getjstring(args[2]), "\n    [2]", getjstring(args[3]), "\n    [3]", getjstring(args[4]), "\n");
            },
            onLeave: function (retval) {
                console.log("orThat_result:", getjstring(retval));
            },
        });

        Interceptor.attach(Module.findExportByName("libhello-jni.so", "Java_com_example_application_DefinitelyNotThisOne_definitelyNotThis"), {
            onEnter: function (args) {
                console.log("definitelyNotThis_args:[1]", getjstring(args[2]), "\n    [2]", getjstring(args[3]), "\n");
            },
            onLeave: function (retval) {
                console.log("definitelyNotThis_result:", getjstring(retval));
            },
        });
    });
}
setImmediate(main);

出flag

ill-intentions（java hook）

GDA

看雪大佬出品的GDA 好用！

还是因为没有修改apk包，触发按钮的Intent显示不了，再次用objection手动开启，找到相对应的进程注入

鼠标点击，即可完成操作

按下中间那个BroadcastIntent，就能hook出flag

Obejction直接注入

发现GDA那个纯属走弯路，直接Objection注入不就好了

objection -g com.example.hellojni explore
>>CLI中输入
android intent launch_activity com.example.application.IsThisTheRealOne
android hooking watch class_method android.content.Intent.putExtra --dump-return --dump-args --dump-backtra
ce

遇到一个问题，就是不知道Intent属于什么类，这个是看了GDA里的脚本后才知道的（android.content.Intent），如果想要直接注入的话，需要andriod的开发经验

bilibili-1024-技术对抗赛第6题(2021年)

参考了 https://www.bilibili.com/read/cv13720199/

大佬的脚本少写启动命令，当时折腾一个早上没解决出来

function hook_native() {
    Java.perform(function(){
        var str0;
        var arg1;
        Interceptor.attach(Module.findExportByName("libc.so", "__system_property_get"), {
            onEnter: function (args) {
                str0 = Memory.readCString(args[0]);
                arg1 = args[1];
                if(str0.indexOf('ro.product.cpu.abi')!=-1||str0.indexOf('ro.build.version.release')!=-1){
                console.log('arg0 '+str0)
                }
            },

            onLeave: function (retval) {
                if(str0.indexOf('ro.product.cpu.abi')!=-1){
                    var before = Memory.readCString(arg1);
                    Memory.writeUtf8String(arg1, "x86");
                    var after = Memory.readCString(arg1);
                    console.log('retval:','before',before,'after',after)
                }else if(str0.indexOf('ro.build.version.release')!=-1){
                    var before = Memory.readCString(arg1);
                    Memory.writeUtf8String(arg1, "9");
                    var after = Memory.readCString(arg1);
                    console.log('retval:','before',before,'after',after)
                }
            }
        });
    });
}
setImmediate(hook_native);