Firmware downloads and zip encryption passwords for LG Ultrafine 4k and 5k displays

lg-ultrafine-4k-and-5k-monitor-firmware.md

https://lmu.lge.com/ExternalService/lgscreenmanager/mac/FW/22MD4KA_MP7/FWLatestVersion.txt https://lmu.lge.com/ExternalService/lgscreenmanager/mac/FW/27MD5KA_MP4/FWLatestVersion.txt https://lmu.lge.com/ExternalService/lgscreenmanager/mac/FW/27MD5KL_TBT_PD/FWLatestVersion.txt https://lmu.lge.com/ExternalService/lgscreenmanager/mac/FW/24MD4KL_TBT_PD/FWLatestVersion.txt

https://lmu.lge.com/ExternalService/lgscreenmanager/mac/FW/22MD4KA_MP7/ https://lmu.lge.com/ExternalService/lgscreenmanager/mac/FW/27MD5KA_MP4/ https://lmu.lge.com/ExternalService/lgscreenmanager/mac/FW/27MD5KL_TBT_PD/ https://lmu.lge.com/ExternalService/lgscreenmanager/mac/FW/24MD4KL_TBT_PD/

The zip passwords were quickly found using the strings command. The password for each model consists of the model name followed by !LGahslxjqlalfqjsgh!@#:

• 22MD4KA!LGahslxjqlalfqjsgh!@#
• 24MD4KL!LGahslxjqlalfqjsgh!@#
• 27MD5KB!LGahslxjqlalfqjsgh!@#
• 27MD5KL!LGahslxjqlalfqjsgh!@#

I've recently bought a used LG 27MDKLA which I use with its original 2m active thunderbolt cable from a M4 Pro Macbook (Tahoe).

LG Screen Manager couldn't update the firmware (freezing at 20%), I've download the 3.10 version zip file from this topic, put it on the screen manager (without unzipping). Result is the same by freezing at 20%. I don't know if the 3.10 version is currently the latest or if I need to find the password of the file.

Could you help me the find the latest firmware and the solution to update? Thanks @jamesxsc @cstrouse

I've recently bought a used LG 27MDKLA which I use with its original 2m active thunderbolt cable from a M4 Pro Macbook (Tahoe).

LG Screen Manager couldn't update the firmware (freezing at 20%), I've download the 3.10 version zip file from this topic, put it on the screen manager (without unzipping). Result is the same by freezing at 20%. I don't know if the 3.10 version is currently the latest or if I need to find the password of the file.

Could you help me the find the latest firmware and the solution to update? Thanks @jamesxsc @cstrouse

The issue is a bug double-freeing memory during programming of the scaler. I patched the app and ran successfully on my M3 Max running Tahoe: https://xscgroupltd368-my.sharepoint.com/:u:/g/personal/james_xsc_co_uk/IQDe5JyTr9N-QJFSNCQ2V3ucAcYAvsAWSKgPGnzgiVMuRi8?e=FTu38A

You may need to bypass security/ manually re-sign it to run it.

If that doesn't fix it, you'll want to look for crash reports e.g. ~/Library/Logs/DiagnosticReports/LG Screen Manager-2026-02-27-142637.ips

I've recently bought a used LG 27MDKLA which I use with its original 2m active thunderbolt cable from a M4 Pro Macbook (Tahoe).
LG Screen Manager couldn't update the firmware (freezing at 20%), I've download the 3.10 version zip file from this topic, put it on the screen manager (without unzipping). Result is the same by freezing at 20%. I don't know if the 3.10 version is currently the latest or if I need to find the password of the file.
Could you help me the find the latest firmware and the solution to update? Thanks @jamesxsc @cstrouse

The issue is a bug double-freeing memory during programming of the scaler. I patched the app and ran successfully on my M3 Max running Tahoe: https://xscgroupltd368-my.sharepoint.com/:u:/g/personal/james_xsc_co_uk/IQDe5JyTr9N-QJFSNCQ2V3ucAcYAvsAWSKgPGnzgiVMuRi8?e=FTu38A

You may need to bypass security/ manually re-sign it to run it.

If that doesn't fix it, you'll want to look for crash reports e.g. ~/Library/Logs/DiagnosticReports/LG Screen Manager-2026-02-27-142637.ips

The app that you'd patched worked perfectly. At now, both version of apps show as "the software is currently up to date" (3.10,1.13,5237,3.05,0,1e for LG Ultrafine 27MD5KA). Thank you @jamesxsc

Currently on Tahoe 26.3:
All resolution, sleep/wake and USB functions work perfectly.
Only ALS Function isn't working as on the previous firmware. I don't know if this is a hardware or software issue, I suppose the disabled auto brightness function is common.

Both the version of Screen Manager in the app store and the above patched version crash updating the firmware at 80% on Tahoe 26.4 with my 27MD5KL (3.04,2.23,5250,4.15,0.3,43,6.59)
https://www.dropbox.com/scl/fi/48xhzlgu8p9g5d4btd98w/LG-Screen-Manager_2026-04-09-153241_Booty.cpu_resource.diag?rlkey=05wol6uebduxuisvn2fnhbain&dl=0

After updating to Tahoe 26.4.1 the monitor software version successfully updated to 3.14 using the above patched version.

After updating to Tahoe 26.4.1 the monitor software version successfully updated to 3.14 using the above patched version.

glad - i don't have a -KL to test !

Hi, I am having trouble downloading firmware for 22MD4K. It gives me error “NotAllowedPage”. Can someone help pls. Thx in advance

Looking for firmware for 34GN850. Main thread on this monitor I could find was this: https://www.reddit.com/r/ultrawidemasterrace/comments/qgbris/lg_34gn850bhow_to_update_firmware/

Is it freezing at 20% and then crashing? If so I can help @ramendog @lalitkapoor

That's what's happening to me, @jamesxsc

Tried the patched version. Update button still fails at 20%. I've downloaded the firmware from the link above, but I can't figure out what file to open with the updates? I tried the zip file itself, and tried looking in each unzipped folder, and there's nothing the updater is happy to work with.

I needed to reboot after installing the patched version. I suspect because of the lghub_updater background process that auto-spawns itself even if you force-quit (which I think was keeping the broken version running in the background even after installing the patched version, until I restarted). Got the firmware updated, and this fixed my wake issues with an LG 27MD5KL. Thank you!

27MD5KL-B and Tahoe 26.5.1. I tried the update using the patched app above, and it was able to get past the 20% hang I was experiencing with the stock LG Screen Manager app, so thank you!

But, when I try to update using the patched app, it reaches about 85% then stops the upgrade and shows the following:

I've tried unplugging the monitor from power and USB, waiting 5min, upgrading again - same issue. Anything else I can do?