CVE-2026-128076nuxt improper output encoding
CVE-2026-128076 is a improper output encoding in nuxt, rated low (3.1 on CVSS 3.1).
Why this priority: Low severity, with no exploitation signal.
Published · Updated · NVD status: Awaiting Analysis
What it is
Output is not encoded for where it lands, so data can be read as markup or commands.
How it is reached
An attacker can exploit it over the network, without an account, but someone has to act first, such as opening a file or following a link. Success also depends on conditions the attacker does not fully control.
What an attacker gains
The direct impact is limited: partial access to data or a partial outage. In practice, this kind of flaw lets an attacker act inside a signed-in user's browser session.
Is it being exploited?
There is no public report of exploitation yet.
What to do
- Upgrade nuxt to a fixed version for your release line (4.0.0, 4.6.4). Other affected products have their own fixed versions on this page.
- Until it is patched, keep it off the internet or behind a VPN, allowlist or authenticating proxy.
- Warn the people who use it, and filter files and links on the way in.
Description from NVD
Nuxt is an open-source web development framework for Vue.js. From 3.21.6 to before 4.0.0 and from 4.4.6 until 4.6.4, the /__nuxt_island path hash uses ohash serialization that does not escape quotes in string values or delimiters in object keys, allowing different island-prop tuples to produce the same path. For prerendering, substituted content is written into the generated page only if the crawler reaches a colliding URL before rendering the page with the legitimate props. Separately, a CDN or reverse proxy that keys island responses by path alone can be primed with the colliding response. If the substituted prop reaches v-html, innerHTML, or another unsafe HTML sink, the response can execute script in the application origin; otherwise the impact is content substitution. Applications that do not use server components or NuxtIsland, islands without attacker-influenced string props, and responses not cached by path alone are unaffected. This issue is fixed in version 4.6.4.
What this means for your architecture.
A CVE names a product. Whether it matters depends on where that product sits in your systems: what reaches it, which trust boundary it guards and what it can reach once compromised. Veriom maps your components, their relationships and your trust boundaries from your code, cloud and delivery evidence, so you can see where a component like this sits. The radar itself does not look at your systems.
Components it touches
- Web front ends and single-page apps. The flaw sits between a user's browser and the web application.
- Admin consoles served to a browser. The flaw sits between a user's browser and the web application.
Trust boundaries in play
- Internet-facing entry points. No account is needed. Any instance reachable from outside your perimeter, through a load balancer, gateway, VPN or exposed admin port, is in scope.
- People who open files and links. Mail, chat and browsers are the delivery path.
- Between a user's browser and the web application. An attacker who crosses it can act inside a signed-in user's browser session.
Questions to answer about your own systems
- Where does nuxt run in your systems, and at which version?
- Which of those instances can be reached from the internet or partner networks?
- What can it reach once compromised: which data stores, secrets and services?
Read more
Sources
- CVE records and CVSS scores from the NVD CVE API. This product uses the NVD API but is not endorsed or certified by the NVD.
- Exploitation status from CISA’s Known Exploited Vulnerabilities catalog.
- Exploit likelihood from FIRST’s Exploit Prediction Scoring System (EPSS), refreshed daily.
- Explanations are written by Veriom from fixed templates over each record’s data, not by a person reviewing each CVE. Descriptions are quoted from the records as published.