Release ASUS RT-AX59U Firmware version 3.0.0.4.388_33950 (2025/09/09)

[fruitcornbread]

Version 3.0.0.4.388_33950
40.39 MB
2025/09/09

Important: After installing this firmware, we strongly recommend performing a factory-default reset to activate every new security adjustment.

Security Enhancements
- Password Policy Upgrade – Minimum of 10 characters, including at least one letter, one digit, and one special character; disallows consecutive identical characters; hardens defense against brute-force attacks.
- HTTPS on 8443 – Management interface now served over TLS by default.
- UPnP Disabled – Universal Plug and Play starts in the off state for reduced surface exposure.
- AiCloud Authentication Hardening (CWE-287) – Added layered verification.
- Authentication Logic Refactor – Removed redundant code paths for a lean sign-in flow.
- Memory Safety Guard (CWE-476) – Introduced null-reference protections across critical services.
- Enhanced IPsec Parameter Validation – The existing input checks have been hardened.
- Data Exposure Mitigation (CWE-200) – Reinforced controls on sensitive pathways.
- Detailed Audit Trails – Expanded logging within the authentication module.

System Improvements
- Connection Stability – Core algorithms refined for steadier links.
- Scheduling Accuracy – Timed tasks execute reliably under PPPoE, PPTP and L2TP WAN modes.
- Client List Maintenance – Resolved an issue that prevented offline devices from being removed from the client list

ZIP SHA-256 : 6C7FD6FBA7D1C676FA626D9A043DC88C3CC9F450AD7DFD615C54362C7A9A0B07
FW SHA-256 : f034c34bf9e08ef4fc47af4a6867b857b125facad1d787f076b5a0f634448f4f

Download: https://dlcdnets.asus.com/pub/ASUS/wireless/RT-AX59U/FW_RT_AX59U_300438833950.zip?model=RT-AX59U

RT-AX59U｜WiFi Routers｜ASUS Global

Discover the RT-AX59U WiFi 6 router's power with advanced features, AiProtection Pro, and seamless AiMesh coverage for an unmatched tech experience.

www.asus.com

 

[bingoshrimp]

I have been looking forward to this update, thinking that this would be the version where the previous WIFI connection problems introduced in March would be fixed. I was especially hopeful considering the line in the changelog specifically mentioning "Connection Stability".

Not so much.

Having run the update for something like 2 days the new firmware I can say there are still clearly problems. They are intermittent, but definitely there:

• Web pages with a lot of media, like news sites or social media: Images or videos often don't load instantly, instead showing placeholders for what seems like several minutes before finally loading.
• Casting steams via Chromcast: There are problems getting the initial connection up and running, often requiring several attempts.

I even did a hard reset after the update, setting up everything manually afterwards. Also, seeing the other firmware update thread here about the AX4200 router, which I get the impression is quite similar to the AX59U, I forced 2.4G band to channel 6, and 5G to channel 36. No dice.

If I'm being honest, there's probably a tiny bit of improvement from earlier versions; images and videos that are stuck in loading actually do seem to end up loading in the end, albeing after the long delay. This of course doesn't mean the experience is anywhere near good enough.

I'm at my wits end here. I cannot for the life of me understand how this is still a problem since March. The last FW update to work flawlessly was 33407, but seeing all the security updates in this new firmware, it feels like it would be a bad idea to go back to the old version.
Or maybe there's a small setting or workaround to make WIFI work again? I tried nearly everything with the earlier problematic firmware 903, but I can't be bothered to go through the same trial and error process again, when it looks like this is just a blunder of epic proportions from Asus' side.

 

[KrypteX]

@bingoshrimp I suggest OpenWrt, it solved all outstanding problems, my AX59U has been rock solid for months. I can't really understand why would anyone run AsusWrt on it.

 

[bingoshrimp]

Well, I can. I have no idea of the scope of the task of setting up something custom on my router. What if something breaks the router? How long will the process take, i.e. how long will I have to go without internet access? What if there are incompatibilities with some of my devices? What features will I lose? Will I lose my warrenty?

I have a million more of those questions, and I don't really have the luxury of time to look into it, let alone the recovery process if something breaks.

I chose a reputable company (at least I though) so that I got something that just works. And.. it kinda does. I mean, I have had no complaints aside from the enormous blunder the general browsing experience being broken...

But why can't they just fix it? The answer for the common user cannot be to jump ship and perform an advanced(?) setup of running custom firmware on the router, can it? Why would that be an absolutely valid thing to suggest?

 

[KrypteX]

@bingoshrimp I only gave you my own experience with the device, it was a friendly suggestion, that's all. But at the end of the day, it is entirely your choice what you do with your router. AFAIK Broadcom-based Asus units are being used by many with Merlin's firmware and Mediatek-based ones (such as the AX59U, TUF-AX4200 and AX6000) are flashed with OpenWrt because OpenWrt has very good support for MediaTek.
These choices work best and many users specifically buy Broadcom/Mediatek to flash Merlin/OpenWrt on them.

If you choose to go with OpenWrt, I can help if you want (just PM me), but I cannot give you any warranty or spend too much of my time on this. If you do it right, it shouldn't take more than 1-2 hours.

 

[UltrashRicco]

I have a TUF-AX6000 with basically the same issues here.
I have to agree with @bingoshrimp on this one, I expect Asus to fix these issues that have been ongoing since March, without having to resort to third-party firmware.

@KrypteX is also right, OpenWRT probably fixes these issues, has more frequent updates, may be safer and more stable, etc. BUT, in my very own past experience with my former DLINK router, which I tried OpenWRT on, it is definitely not an easy experience for a beginner expecting to have a working router out of the box, and requires quite a bit of involvement to get anything done or working, as @bingoshrimp seems to be well aware of: installing (especially complex with DLINK routers), getting WiFi to work, reverting back to the OEM firmware, etc. Everything required checking the documentation extensively.

I experienced performance issues, and back in the day (a couple of years back), WiFi 5 was not even supported either by OpenWRT itself or by the drivers for my (MediaTek) chipset if I am not mistaken. I eventually reverted to the OEM firmware.
I only dared to try in the first place because I had my ISP's working stock router as a backup and was curious about the praised OpenWRT.

If you need total control over your router and being able to run apps on it (which is great and can replace a Raspberry Pi for things like PiHole or PiVPN), it is definitely a perfectly valid alternative, especially once your router is deprecated and no longer receives updates. BUT, I do not think it is wise to recommend OpenWRT without a word of warning regarding the level of knowledge and involvement required, and without having a working backup router to rely on.

I have no device on which to install Merlin so I am unable to try it, but it seems like it could be the best of both worlds, with configurability, being able to run apps, a user interface that remains quite user-friendly and I guess a working default configuration. However, this is not a solution that is applicable to MediaTek-based devices unfortunately.

Also, thank you @bingoshrimp for your feedback regarding FW version 3.0.0.4.388_33950. I have been expecting its release for the TUF-AX6000 but nothing so far. I intend to test it upon release to check whether the connectivity issues still persist, as with the 2 previous releases. Given your feedback, this does not look too promising though.

 

[KrypteX]

The time you guys take to write down your complaints would be enough to flash OpenWrt. Add 1 more hour of documentation and you're ready to go with a full manual setup. No joke

OpenWrt SNAPSHOT builds come with kernel 6.12 already and have pretty good performance thanks to hardware/software flow offloading (HFO/SFO) on MediaTek and Qualcomm-based units. Ethernet and WiFi are quite stable on MediaTek-based Asus units, in particular.

Also keep in mind that Merlin only supports Broadcom-based Asus units.

Anyway and anyhow... I won't try to convince you of anything. I just couldn't accept a router in my home that's basically broken since March lol. Would have thrown it out a looong time ago, for sure.

 

[bingoshrimp]

@KrypteX I'm sorry if it might have felt like I was attacking you somehow; I wasn't, I was merely a bit frustrated. Your input is greatly appreciated, and I do believe that I could have probably been well up and running with openWRT with the time and energy I've spent being frustrated with Asus

Having thought about it a bit, I probably could see myself tinker with some custom firmare - I just didn't buy it for that purpose, you know. And I would absolutely need a spare router to have things running while setting the router up, like @UltrashRicco mentions.

Would you believe I actually sent my ISP router back when I got the Asus router because I finally had my own "way better gear" - talk about a bad decision

Anyway, I think I'm done complaining about the whole thing now that I've realized Asus routers are something to steer clear of. I will stick to 33407 firmware for the time being and try out the next firmware version when it arrives; if it works, great, if not, I might just go ahead and try OpenWRT. If I can't get that project off the ground for some reason, well, let's just say I'm thoroughly warming up to the idea of some more expensive gear anway.

@UltrashRicco I'm sorry you seem to find yourself in the same situation with your router - we don't deseve this god awful Asus incompetency With no end in sight of the barrage of bad firmware, maybe now is as good a time as ever to revisit OpenWRT

 

[UltrashRicco]

@bingoshrimp I am fine with FW 3.0.0.4.388_33427 (for the TUF-AX6000) which has always been very stable, as were all the versions before, which installed and performed seamlessly without even my knowledge. I started having issues with 3.0.0.4.388_33903, as, I guess, everyone with auto-updates still enabled, which is probably most users.

Asus did drop the ball on this one, big time, likely affecting many users. Too bad, I'll think twice before purchasing anything Asus again. I am quite happy with the older FW, however the issue is the potential security risks running an "old" firmware...

I will most likely give OpenWRT another try at some point, definitely when the router is deprecated and no longer supported, but it feels like it is the case already somehow.

I checked the OpenWRT documentation regarding the AX6000 and apparently reverting back to the OEM FW does not seem to be very complicated (much easier than with DLINK), straight from the UI (after installing a dedicated package). It should apply to your AX59U too but you should better triple check.
Basically, as long as you export your current Asus FW settings, it should not be too risky to try OpenWRT and restore the Asus FW and restore your settings in case it does not meet your expectations, and go back to your current setup in no time.

 

[KrypteX]

@bingoshrimp @UltrashRicco Hey guys, I'm sad to see you having great hardware and struggling to move ahead because of bad software/firmware.
Using old firmware can come with serious security issues, so I really don't recommend running 33407/33427 from 2024, even if it's stable.
If you decide to, I can help with moving over to OpenWrt. Drop me a PM and I'll do my best to guide you. Cheers!