Disable-web-security in Chrome 48+ - google-chrome

Question

I have a problem with the --disable-web-security flag. It is not working in Chrome 48 and Chrome 49 beta on Windows.
I've tried killing all of the instances, reboot and run Chrome with the flag first of all, tried different machines as well. In the beta I can see the warning popup ("You are using unsupported flag.."), but CORS is still being enforced. Public version seems to ignore the flag completely.
There seems to be no news or people reports about that, so it might be a local issue.
Will be grateful for help or any related info.

Answer 1

Update 2021-10-18
As of Chrome 95, on MacOS and Windows, --disable-site-isolation-trials remains a required flag in order to disable web security, so the command-line arguments to Chrome seen below are still valid. (Some of the arguments are not formally supported by Chrome, as it will warn you.)
To test whether you've successfully launched Chrome with web security disabled, run the snippet in Web Security Test at the bottom of this post.
Update 2020-04-30
As of Chrome 81, it is mandatory to pass both --disable-site-isolation-trials and a non-empty profile path via --user-data-dir in order for --disable-web-security to take effect:
# MacOS (in Terminal)
open -na Google\ Chrome --args --user-data-dir=/tmp/temporary-chrome-profile-dir --disable-web-security --disable-site-isolation-trials
# Windows (from "Run" dialog [Windows+R] or start menu in Windows 8+)
chrome.exe --user-data-dir=%TMP%\temporary-chrome-profile-dir --disable-web-security --disable-site-isolation-trials
(Speculation) It is likely that Chrome requires a non-empty profile path to mitigate the high security risk of launching the browser with web security disabled on the default profile. See --user-data-dir= vs --user-data-dir=/some/path for more details below.
Thanks to #Snæbjørn for the Chrome 81 tip in the comments.
Update 2020-03-06
As of Chrome 80 (possibly even earlier), the combination of flags --user-data-dir=/tmp/some-path --disable-web-security --disable-site-isolation-trials no longer disables web security.
It is unclear when the Chromium codebase regressed, but downloading an older build of Chromium (following "Not-so-easy steps" on the Chromium download page) is the only workaround I found. I ended up using Version 77.0.3865.0, which properly disables web security with these flags.
Original Post 2019-11-01
In Chrome 67+, it is necessary to pass the --disable-site-isolation-trials flag alongside arguments --user-data-dir= and --disable-web-security to truly disable web security.
On MacOS, the full command becomes:
open -na Google\ Chrome --args --user-data-dir= --disable-web-security --disable-site-isolation-trials
Regarding --user-data-dir
Per David Amey's answer, it is still necessary to specify --user-data-dir= for Chrome to respect the --disable-web-security option.
--user-data-dir= vs --user-data-dir=/some/path
Though passing in an empty path via --user-data-dir= works with --disable-web-security, it is not recommended for security purposes as it uses your default Chrome profile, which has active login sessions to email, etc. With Chrome security disabled, your active sessions are thus vulnerable to additional in-browser exploits.
Thus, it is recommended to use an alternative directory for your Chrome profile with --user-data-dir=/tmp/chrome-sesh or equivalent. Credit to #James B for pointing this out in the comments.
Source
This fix was discovered within the browser testing framework Cypress: https://github.com/cypress-io/cypress/issues/1951
Web Security Test
Run this snippet to confirm that this solution actually disabled web security in Google Chrome:
window.addEventListener("DOMContentLoaded", () => {
const iframe = document.querySelector("iframe");
iframe.addEventListener("load", () => {
const canAccessIframeDocument = !!iframe.contentDocument;
document
.querySelector(
canAccessIframeDocument ? ".security-disabled" : ".security-enabled"
)
.classList.remove("hidden");
});
// To ensure the `load` event always fires, only set iframe src after the
// event listener is attached.
iframe.src = "https://google.com";
});
body {
font-family: sans-serif;
}
.hidden {
display: none;
}
/* Web security should normally be enabled, so this is colored green, despite
the objective of this solution to disable it. */
.security-enabled {
font-weight: bold;
color: darkgreen;
}
.security-disabled {
font-weight: bold;
color: darkred;
}
<h1>Web Security Test</h1>
<p>
This test attempts to access the inner contents of a cross-origin iframe,
which is normally disallowed.
</p>
<p class="security-enabled hidden">
Web security is enabled. The cross-origin iframe document could not be
accessed.
</p>
<p class="security-disabled hidden">
Web security is disabled. The cross-origin iframe document was
successfully accessed.
</p>
<iframe class="hidden">
Iframes are not supported.
</iframe>

Answer 2

I'm seeing the same thing. A quick google found this question and a bug on the chromium forums. It seems that the --user-data-dir flag is now required.
Edit to add user-data-dir guide

Answer 3

Mac OS:
open -a Google\ Chrome --args --disable-web-security --user-data-dir=
UPD: add = to --user-data-dir because newer chrome versions require it in order to work

Answer 4

On OS X, to open a new Chrome window - without having to close the already open windows first - pass in the additional -n flag. Make sure to specify empty string for data-dir (necessary for newer versions of Chrome, like v50 something+).
open -na /Applications/Google\ Chrome.app/ --args --disable-web-security --user-data-dir=""
I found that using Chrome 60+ on Mac OS X Sierra, the above command no longer worked, but a slight modification does:
open -n -a /Applications/Google\ Chrome.app/Contents/MacOS/Google\ Chrome --args --user-data-dir="/tmp/chrome_dev_sess_1" --disable-web-security
The data directory path is important. Even if you're standing in your home directory when issuing the command, you can't simply refer to a local directory. It needs to be an absolute path.

Answer 5

The chosen answer is good, but for those who are still struggling with what they are talking about(your first time dealing with this issue), the following worked for me.
I created a new shortcut to Chrome on my desktop, right clicked it, and set the "Target" field to the following,
"C:\Program Files (x86)\Google\Chrome\Application\chrome.exe" --disable-web-security --user-data-dir="c:/chromedev"
The directory can be anything you want, I decided to make an empty folder called chrome dev in my C: directory. It has nothing to do where chrome is installed on your computer. It's just a fluff type thing.
This link also has clear directions for other OSes. How to disable web securityin Chrome

Answer 6

The version 49.0.2623.75 (64-bit) is not in beta anymore.
The command to fix the CORS issue is
google-chrome-stable --disable-web-security --user-data-dir

Answer 7

Install This Chrome-plugin for Disable-web-security in Chrome::
" Allow-Control-Allow-Origin: * "
link Here or you can google above plugin if you want.
it is very easy to enable and disable the security with this plugin.

Answer 8

For Chrome Version 50+ for Mac Users. Close all opened chrome first and run the below command
open -a Google\ Chrome --args --disable-web-security --user-data-dir=""
The above will work. Thanks

Answer 9

For Mac, using Safari is a good alternate option for local development purpose and the feature is built into the browser (so no need to add browser extension or launch Chrome using bash command like [open -a Google\ Chrome --args --disable-web-security --user-data-dir=""].
To disable cross origin restriction using Safari (v11+): From menu click “Develop > Disable Cross Origin Restriction”.
This does not require relaunching the browser and since its a toggle you can easily switch to secure mode.

Answer 10

From Chorme v81 the params --user-data-dir= requires an actual parameter, whereas in the past it didn't.
Something like this works fine for me
"C:\Program Files (x86)\Google\Chrome\Application\chrome.exe" --disable-web-security --user-data-dir="\tmp\chrome_test"

Answer 11

In a terminal put these:
cd C:\Program Files (x86)\Google\Chrome\Application
chrome.exe --disable-web-security --user-data-dir="c:/chromedev"

Answer 12

As of the date of this answer (March 2020) there is a plugin for chrome called CORS unblock that allows you to skip that browser policy. The 'same origin policy' is an important security feature of browsers. Please only install this plugin for development or testing purposes. Do not promote its installation in end client browsers because you compromise the security of users and the chrome community will be forced to remove this plugin from the store.

Answer 13

For MacOSX
open -n -a /Applications/Google\ Chrome.app/Contents/MacOS/Google\ Chrome --args --user-data-dir="/tmp/chrome_dev_sess_1" --disable-web-security
For Windows 10+
"C:\Program Files (x86)\Google\Chrome\Application\chrome.exe" --disable-web-security --disable-gpu --user-data-dir=~/chromeTemp

Answer 14

It working for me.
Try using this..it will help you out..
c:\Program Files\Google\Chrome\Application>chrome.exe --disable-web-security --user-data-dir="D:\chrome"

Answer 15

For Windows
C:\Program Files\Google\Chrome\Application> .\chrome.exe --disable-web-security --disable-gpu --user-data-dir=~/chromeTemp