The biggest security consideration around angular-ui-router is not the library itself but the framework underneath it: angular-ui-router routes AngularJS 1.x applications, and AngularJS reached end of life in January 2022. The router is a mature, widely used package with sustainable maintenance, but a routing library can only be as secure as the framework it plugs into. If your app still runs on AngularJS 1.x, the router is stable while the platform below it no longer receives security patches. That is the dependency risk worth understanding.
What angular-ui-router is
angular-ui-router is the de facto flexible routing solution for AngularJS 1.x, offering nested views and state-based routing that the built-in ngRoute never matched. It models your UI as a state machine rather than a flat list of URLs, which is why non-trivial single-page apps adopted it heavily. On npm it still pulls tens of thousands of weekly downloads, a decade after AngularJS peaked, because a lot of production software never migrated off it.
One naming point trips people up. The package published as angular-ui-router corresponds to the older 0.x line. For the 1.0+ releases you install @uirouter/angularjs instead. The underlying project also expanded into @uirouter/core, which powers routers for Angular (2+) and React through separate bindings. So "UI-Router" is a family; angular-ui-router specifically is the AngularJS 1.x member.
The real risk: an end-of-life framework
Here is the uncomfortable part. The Angular team ended long-term support for AngularJS 1.x on December 31, 2021. After that date, no new versions of AngularJS itself ship, including for security issues. That does not make your app insecure overnight, but it does mean any newly discovered vulnerability in AngularJS core will never be patched upstream.
For a routing library like angular-ui-router, this matters because routing sits directly on top of framework primitives: the digest cycle, $location, template compilation, and expression evaluation. AngularJS expression sandbox bypasses were a recurring class of issue during its supported life. With the framework frozen, you inherit whatever residual exposure remains and cannot rely on an upstream fix.
The router being "actively maintained" is genuinely good news, but it is a narrow reassurance. A patched router on an unpatched framework is a locked door in a house with no walls.
Auditing what you actually depend on
Before deciding anything, inventory the situation. Two commands tell you most of what you need:
# what version, and is the tree healthy?
npm ls angular-ui-router @uirouter/angularjs
# known advisories across the whole dependency tree
npm audit --production
npm audit checks your entire tree against the advisory database, which is the point: the router's own record may be clean while AngularJS or another transitive dependency carries a known issue. A standalone SCA scan does the same continuously and, unlike a one-off npm audit, keeps watching as new advisories are published against packages you already shipped.
Pin the version you resolve to and commit the lockfile. An EOL ecosystem is exactly where you do not want a floating ^ range silently resolving to something untested.
{
"dependencies": {
"@uirouter/angularjs": "1.1.2"
}
}
Reducing exposure without a full rewrite
Migrating a large AngularJS app to modern Angular or React is a multi-quarter project, and telling a team to "just rewrite it" is rarely useful advice. Several lower-cost measures reduce exposure in the meantime.
Lock down what the router renders. UI-Router resolves templates and controllers per state; make sure no state renders a template path or component name derived from unsanitized URL input, which would be a template-injection foothold. Treat route parameters as untrusted, the same as any other user input, and validate them in resolve functions before they reach a view.
Add a strict Content-Security-Policy at the HTTP layer. A good CSP blunts the impact of a script-injection bug even on an unpatched framework by refusing to execute inline or third-party scripts you did not allow.
Freeze and monitor the dependency tree. Because upstream will not ship fixes, your defense is knowing immediately when a new advisory lands against something you use, so you can mitigate at the application or infrastructure layer.
When migration is the answer
If the application is strategic and long-lived, the durable fix is migrating off AngularJS entirely. UI-Router smooths this because @uirouter/core and the Angular and React bindings share concepts, so your mental model of states and transitions carries over even as the framework changes. The AngularJS upgrade guide's hybrid approach (running AngularJS and modern Angular side by side via ngUpgrade) lets you migrate route by route rather than in one risky cutover.
Treat the EOL framework as the forcing function it is. angular-ui-router will keep working, but "keeps working" and "keeps being safe to expose to the internet" are different claims. For libraries broadly, our academy covers how to evaluate the maintenance health of a dependency before you commit to it.
FAQ
Is angular-ui-router deprecated?
The library itself is not deprecated and remains maintained, though for 1.0+ you should install @uirouter/angularjs rather than the legacy angular-ui-router package. The deeper issue is that AngularJS 1.x, which the router depends on, reached end of life in January 2022.
Does angular-ui-router have known vulnerabilities?
The router's own advisory record is comparatively clean. The practical risk comes from running it on AngularJS 1.x, which no longer receives upstream security patches, so any new framework-level vulnerability will go unfixed. Run npm audit against your full tree to see current advisories.
What is the difference between angular-ui-router and @uirouter/angularjs?
They are the same project at different versions. angular-ui-router is the older 0.x line; @uirouter/angularjs is the 1.0+ package for AngularJS 1.x. The broader UI-Router family also includes @uirouter/core with bindings for modern Angular and React.
Should I migrate off angular-ui-router?
If the app is long-lived and internet-facing, yes, because the underlying AngularJS framework is end-of-life. UI-Router's shared core concepts make migrating to Angular or React bindings less disruptive, and a hybrid ngUpgrade path lets you move incrementally rather than in one rewrite.