Alby Hub Users Told to Restrict Access and Update Wallet

Bitcoin wallet company Alby has warned of a critical Alby Hub vulnerability that could let an attacker take over a wallet and send its funds, but only when the owner has made the Hub reachable from the public internet. The Hacker News reported the warning. Alby Hub is a self-hosted Lightning wallet. Self-hosted means the owner runs the wallet software on their own computer or server instead of using a service run by Alby, and a Lightning wallet is software for holding and sending bitcoin over the Lightning network, a payment layer built on top of bitcoin.

According to Alby, the flaw affects Alby Hub versions v1.7.0 through v1.18.5, all released before August 2025. Alby said one user has been affected so far, and that the user reported the details to the company. Versions v1.19.0 and later do not have the flaw. The first release containing the fix was published on August 29, 2025, so any Hub running a release published since that date is not affected. Alby has not yet described the technical cause of the flaw. It said it would publish full details later in line with responsible disclosure, a practice that gives vendors time to fix a problem before technical detail is made public, and it thanked researchers who reported other issues fixed in the latest release.

Alby is asking anyone still on an older build to act in a specific order. First, stop outside access to the Hub's management interface, the web page used to control the wallet. In a Docker setup this means the port should be published as 127.0.0.1:8080:8080, not 8080:8080, so the interface is reachable only from the machine itself. Docker is a tool that packages software into containers so it runs consistently across computers, and a port is a numbered channel through which the web interface is served. On a cloud server, which is simply a rented remote computer, the firewall rule for port 8080 should allow only the owner's own address rather than any address. A firewall is a security control that decides which network traffic may reach a service. Second, update to v1.24.0, the current release. Third, if the Hub ran an affected version and was reachable from the internet, change the unlock password after the update and contact Alby at security@getalby.com.

Alby has not said whether updating alone ends any access an attacker already had to an exposed Hub. The advice to change the unlock password applies exactly to that group, and the report notes that no published source explains what the password change is meant to undo. That leaves an open question for anyone who had an affected Hub publicly reachable and may already have been compromised.

How a Hub ends up on the internet is part of the story. Alby Hub is built to sit on a private network. Its web interface requires a login, but the project's own documentation now warns owners not to put it on the public internet because the server listens on every network connection the machine has, rather than only on the machine itself. That is a meaningful distinction: a program that listens on localhost is visible only to the same computer, while one that listens on all network interfaces can answer requests from every address the computer can reach. The warning is new. It arrived in a documentation change merged on September 7, whose description said several setup guides had described the server as running on localhost when it actually listens on all network interfaces. The same change switched the project's Docker file from publishing port 8080 to every address to publishing it only to the machine itself.

Before that change, the guide for running Alby Hub on a Linux server said the Hub runs on localhost and recommended a reverse proxy for anyone who wanted to make it public. A reverse proxy is a server that sits in front of another application and forwards outside requests to it. The README files shipped with the oldest and newest affected releases did not carry that warning, and neither does the one in the current release.

Even after the warning, Alby's own setup guides still described configurations open to the internet as of September 9. The DigitalOcean guide tells the reader to keep the server's public address switched on, saying that is needed to open Alby Hub in the browser, and then to open the Hub at that address. The Hetzner guide walks through creating a firewall rule for port 8080 with the source set to any IPv4 or IPv6 address, or the user's own IP address for better security, and its example Docker file publishes the port to every address. These instructions could leave a Hub reachable to anyone on the public internet, the exact condition Alby now says is unsafe for affected versions.

This is not the first time an exposed Alby Hub has been taken over. In November 2025, replying to a user whose Hub had been emptied, Alby said the machine was reachable publicly on the clearnet, so it could be accessed from the outside. Clearnet means the ordinary public internet, as opposed to a private or anonymized network. By Alby's account, that earlier incident was a different problem, not this flaw: the Hub's setup had never been finished, so no unlock password existed yet, and the attacker completed the setup themselves. After that case, a change to the Umbrel app put Alby Hub behind Umbrel's own login, which had been switched off for it until then. Umbrel's app store now installs v1.24.0, and Alby's own Umbrel listing installs v1.21.4, both newer than the fixed version, though that describes what those stores install today rather than what any given Hub is running.

The report highlights two questions that remain open. Alby tells people to check the installed version, but that does not indicate whether Alby Cloud has already handled the update for them. Alby also names v1.7.0 as the start of the affected range without saying where that leaves releases before it, which go back to v1.0.2. The Hacker News has asked Alby about both points, along with the question of what the password change is meant to undo.

For anyone running a self-hosted wallet or other internet-facing web application, the practical lesson is to treat a management interface as private unless it is deliberately published to a trusted address. AEU-I offers security-first IT, infrastructure and consulting for teams that want an independent look at how their services are exposed.