Bitwarden "cannot read properties of undefined" (reading to tolowercase)

Totof · September 7, 2025, 5:57pm

I have the same issue. My self-hosted server was in v8.5.0 (not sure about this version, but not more than 8.5.x)

I installed a new PC with the last version of the Bitwarden chrome extension client.(v2025.8.2) => KO (“Cannot read properties of undefined (reading ‘toLowerCase’)”.
But connection through the web application was working fine (same version as my server of course, so v2025.5.x)

My all other PC (3) was working fine as well ! (Web client and legacy chrome extension)

I decided to upgrade my server to the latest version (v8.5.1), with this version the web client being v2025.8.2.

From this upgrade, the web client (2025.8.2) doesn’t work at all. This means that there is a bug into that version.

My legacy PC installed with a legacy client chrome extension work fine in despite this upgrade.

But my new PC still with the last client chrome extension (v2025.8.2) still doesn’t work.

For you information, I decided to install a legacy chrome extension version on the new PC. And the first one that works being the v2025.7.1. The other versions higher than this one doesn’t work. I tried also a v2025.5.0 and it works. So it looks like the issue is present after the v2025.7.1. into the client chrome extension.

Hope that can help you.

nugait · September 8, 2025, 10:14am

Still having issues. Can access using desktop app, but not using web neither extension.
Web 2025.8.2, extension 2025.8.2, desktop app 2025.8.2.

override:

docker-compose.yml:

Thanks

jjmmfi · September 14, 2025, 8:22pm

I got the same issue still. Just updated my self-hosted from 2025.1 to the latest server 2025.8.1, web 2025.8.3.

I get error when using web and browser extention: **An error has occurred.**Cannot read properties of undefined (reading ‘toLowerCase’)

I am also unable to access using the desktop app and both ios and android apps.

I am using the Linux Standard Deployment with Ubuntu 22.04 server.

jjmmfi · September 14, 2025, 9:15pm

Running the latest versions clients (at least seeing no updates on the app stores)

I am not seeing any errors in the Docker container logs when trying to log in, unfortunately.

I have one Chrome extension that is showing this error in the Docker container logs: [bitwarden-api] Error Number:201,State:4,Class:16. It is already logged in and has cached my data in the browser. I get this when I try to add a new login item, and it can’t connect to the server. This browser extention version: Version: 2025.7.0, SDK: ‘main (f2bc708)’, Server version (self-hosted): 2025.1.3

I am able to access the admin portal.

Nail1684 · September 14, 2025, 9:34pm

Do you have two separate servers with different versions now?

The latest Chrome extension version is 2025.8.2.

jjmmfi · September 14, 2025, 10:06pm

That cached extension that has my passords still tries to connect to the old installation. I updated so that does not excist and it is unable to connect. I know it is not the newest version. The point I was trying to make is that there is an issue even with clients that are already logged in before the update if that makes sense.

Hopefully, this will get resolved fast. Happy to provide more info as my password manager is down…

And yes I have also tried with the latest browser extention version on different chrome profile. The 2025.8.2.

ashes · September 15, 2025, 2:32pm

Same issue here with bitwarden self hosted.

Currently with

ghcr.io/bitwarden/nginx:2025.8.1       
ghcr.io/bitwarden/admin:2025.8.1         
ghcr.io/bitwarden/notifications:2025.8.1 
ghcr.io/bitwarden/attachments:2025.8.1   
ghcr.io/bitwarden/sso:2025.8.1             
ghcr.io/bitwarden/icons:2025.8.1           
ghcr.io/bitwarden/identity:2025.8.1        
ghcr.io/bitwarden/web:2025.8.3             
ghcr.io/bitwarden/events:2025.8.1         
ghcr.io/bitwarden/api:2025.8.1             
ghcr.io/bitwarden/mssql:2025.8.1

And if I try to login from web (chrome)

Cheers

dabe · September 17, 2025, 3:44pm

Same here. Latest 2025.8.1 images, all from ghcr.io, and I get this error only when logging in from any browser (chrome and firefox).

Did not have this issue before updating (from 2025.6.1)

dwbit · September 17, 2025, 3:59pm

Hey @dabe just double checking you followed the steps here? What is your Bitwarden browser extension version number?

dabe · September 17, 2025, 4:25pm

Yup. I’m using the bitwarden.sh script and I can see in my bwdata directory in the docker compose files that everything is using ghcr.io images.

I’m not even using an extension, I’m just trying to use the web client login. It says 2025.8.3 at the bottom of the page.

dabe · September 17, 2025, 4:28pm

If I inspect the web traffic I can see the same 400 error from the API as mentioned here An error "Can't access property 'toLowerCase', e.message is undefined" during login to self-hosted instance in Firefox · Issue #16211 · bitwarden/clients · GitHub

{“error”:“invalid_grant”,“error_description”:“Auth-Email header invalid.”}

dabe · September 17, 2025, 4:43pm

Ah, a good ol VM restart fixed the issue. Must’ve been using some cached/old version of something somewhere.

ashes · September 17, 2025, 6:25pm

Problem also solved from my side.

Dont know what was the issue, i removed fail2ban from authelia, and another middleware i had, and restarted authelia and traefik.

It started working

kourosh · September 24, 2025, 5:59am

We still have this on 2025.9.0. i don’t understand why some users are getting this error and some not? what’s the difference between theme?

Nail1684 · September 24, 2025, 10:23am

@Micah_Edelblut mentioned this [PM-24151] Unable to log in to browser extension in Safari, fixes #16211 by enmande · Pull Request #16225 · bitwarden/clients · GitHub as the corresponding fix (?) in a comment on GitHub.

@kourosh Are all your versions (server and all used BW apps) on 2025.9.0 or above?

Micah_Edelblut · September 24, 2025, 10:37am

The underlying issue in users seeing this “cannot read properties of undefined” error is that an error coming down from the server does not come down with the expected message or validationErrors properties. That “fix” resolves the parsing, but wouldn’t necessarily resolve the underlying error because that could be anything.

The reason we are telling folks to update their self-hosted is because the most common recent cause of an error coming down without a message was an incompatibility between recent clients which were not sending up the auth-email header and older servers that require the auth-email header.

Nail1684 · September 24, 2025, 11:11am

Just asking for those who then still see that error: Contact support – and hoping for the best – then it is?

Micah_Edelblut · September 24, 2025, 11:24am

Verify you’re on the latest version of the desktop, browser extension, or web app. If so, and you’re still seeing that error, contacting support is an appropriate step to take. If possible, reporting a bug with detailed replication steps of what the user was doing that lead up to that error would be very helpful to the team.