KEVWire

Security intelligence, with context.

Response snapshot Oct 27, 2026, 03:07 UTC

Back to the wire
Permalink
VulnerabilityCVE-2026-114131

Nuxt: Route rules are matched against the raw request path, so a percent-encoded segment can bypass `appMiddleware` on dynamic and catch-all routes

Nuxt compared `routeRules` keys against the raw request path, without decoding percent-encoding, while the router decodes parameters when it resolves a route.

At a glance

Exploited
Not known
Severity
6.5 Medium (CVSS 3.1)
Chance of exploitation
0.4% in the next 30 days
Sources
1 source

What to do

GitHub lists first patched versions: nuxt: 4.4.4; nuxt: 3.21.4. Confirm the affected range and upgrade guidance in the exact advisory.

Read GitHub-reviewed advisory GHSA-6gq8-jgmh-3ffp (opens a new tab)

What happened

### Summary

Nuxt compared `routeRules` keys against the raw request path, without decoding percent-encoding, while the router decodes parameters when it resolves a route. A request whose path is percent-encoded can therefore resolve to a page while failing to match the route rule meant to protect it, so the rule's `appMiddleware` never runs, including during server rendering.

### Impact

For a page served through a dynamic or catch-all route, an attacker can percent-encode a character in the path to skip the rule:

Continue reading

```ts export default defineNuxtConfig({ routeRules: { '/users/admin': { appMiddleware: 'auth' }, }, }) ```

Requesting `/users/%61dmin` still renders `app/pages/users/[id].vue` with `id` decoded to `admin`, but the rule keyed `/users/admin` does not match, so `auth` does not run and the server renders and returns the gated page to an unauthenticated visitor. No privileges and no user interaction are required, and only ASCII characters are involved.

Purely static ASCII routes are not affected: static segments are matched without decoding, so a request for `/%61dmin` does not resolve to the page registered at `/admin` and 404s instead of rendering.

The rule keys affected are the ones carried in the app manifest and consumed by the app: `appMiddleware`, `redirect`, `appLayout`, `ssr`, `prerender`, and the payload flags derived from `cache`, `isr` and `swr`.

If you have pinned or overridden dependency versions below what your Nuxt release declares, a release outside the affected ranges can still be exposed, so do not conclude from a single reproduction that you are unaffected.

### Patches

Releases from `4.4.4` and `3.21.4` are not affected, because their dependency floor requires a version of the underlying HTTP layer that normalises percent-encoding in the request path before routing, which removes the mismatch in a default install.

The comparison itself is fixed in `nuxt@4.5.2` and `nuxt@3.21.11`: route-rule keys and lookup paths are now decoded (and, unless `router.options.sensitive` is set, case-folded) before they are compared. Reserved escapes such as `%2F` are left encoded, so decoding cannot introduce extra path segments, and paths that cannot be decoded are matched verbatim.

Upgrading to those releases is recommended, since it fixes the comparison rather than relying on a dependency to normalise the input, and it also restores route rules for pages whose paths contain non-ASCII characters.

### Workarounds

If you cannot upgrade, do not rely on a `routeRules` key alone to protect a route. Attach the middleware to the page itself, which binds it to the resolved route rather than to the raw path string:

```vue

```

### Credits

Thanks to @sushi-gif, whose report that route rules keyed with non-ASCII paths never match the routes generated for those pages prompted the review that found this issue.

Affected package ranges reported by GitHub: nuxt: >= 4.0.0, < 4.4.4 nuxt: >= 3.11.0, < 3.21.4

Scores and how they were measured

CVSS base severity

6.5

Version 3.1As of

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Measurement source (opens a new tab)

How bad it is if exploited. Not a prediction of exploitation or proof you are exposed.

EPSS probability

0.4%

Scored Percentile 29.9%

Model and measurement source (opens a new tab)

A model's estimate of exploitation in the next 30 days, not certainty or your own risk.

Related technology

Sources

  1. Primary source

    GitHub-reviewed advisory GHSA-6gq8-jgmh-3ffp (opens a new tab)

    The public advisory supplies the description, affected package/version ranges, and any listed CVSS metric. GitHub review is not local review.

    Published Checked

  2. Primary source

    GitHub public advisory API page (opens a new tab)

    The API page supplied GHSA-6gq8-jgmh-3ffp, its actual identifiers, source dates, and structured metrics.

    Published Date not suppliedChecked

  3. Primary source

    GitHub public advisory API page (opens a new tab)

    The API page supplied GHSA-6gq8-jgmh-3ffp, its actual identifiers, source dates, and structured metrics.

    Published Date not suppliedChecked

  4. Primary source

    GitHub public advisory API page (opens a new tab)

    The API page supplied GHSA-6gq8-jgmh-3ffp, its actual identifiers, source dates, and structured metrics.

    Published Date not suppliedChecked

  5. Primary source

    GitHub public advisory API page (opens a new tab)

    The API page supplied GHSA-6gq8-jgmh-3ffp, its actual identifiers, source dates, and structured metrics.

    Published Date not suppliedChecked

  6. Primary source

    GitHub public advisory API page (opens a new tab)

    The API page supplied GHSA-6gq8-jgmh-3ffp, its actual identifiers, source dates, and structured metrics.

    Published Date not suppliedChecked

  7. Primary source

    GitHub public advisory API page (opens a new tab)

    The API page supplied GHSA-6gq8-jgmh-3ffp, its actual identifiers, source dates, and structured metrics.

    Published Date not suppliedChecked

  8. Primary source

    GitHub public advisory API page (opens a new tab)

    The API page supplied GHSA-6gq8-jgmh-3ffp, its actual identifiers, source dates, and structured metrics.

    Published Date not suppliedChecked

  9. Primary source

    GitHub public advisory API page (opens a new tab)

    The API page supplied GHSA-6gq8-jgmh-3ffp, its actual identifiers, source dates, and structured metrics.

    Published Date not suppliedChecked

  10. Primary source

    GitHub public advisory API page (opens a new tab)

    The API page supplied GHSA-6gq8-jgmh-3ffp, its actual identifiers, source dates, and structured metrics.

    Published Date not suppliedChecked

  11. Primary source

    GitHub public advisory API page (opens a new tab)

    The API page supplied GHSA-6gq8-jgmh-3ffp, its actual identifiers, source dates, and structured metrics.

    Published Date not suppliedChecked

  12. Primary source

    FIRST measured EPSS score (opens a new tab)

    Measured EPSS probability and percentile for CVE-2026-114131, scored 2026-10-26. This is a model estimate, not proof of exposure.

    Published Checked

Cite this record

For factual claims, cite the primary sources above; cite KEVWire for its compilation, dates, and classifications.

APA

KEVWire. (2026, October 22). Nuxt: Route rules are matched against the raw request path, so a percent-encoded segment can bypass `appMiddleware` on dynamic and catch-all routes (CVE-2026-114131). https://kevwire.com/record/CVE-2026-114131

MLA

"Nuxt: Route rules are matched against the raw request path, so a percent-encoded segment can bypass `appMiddleware` on dynamic and catch-all routes (CVE-2026-114131)." KEVWire, 22 Oct. 2026, kevwire.com/record/CVE-2026-114131.

Chicago

KEVWire. "Nuxt: Route rules are matched against the raw request path, so a percent-encoded segment can bypass `appMiddleware` on dynamic and catch-all routes (CVE-2026-114131)." Last modified October 22, 2026. https://kevwire.com/record/CVE-2026-114131.

Evidence summary (plain text)

Nuxt: Route rules are matched against the raw request path, so a percent-encoded segment can bypass `appMiddleware` on dynamic and catch-all routes (Oct 22, 2026).
Nuxt compared `routeRules` keys against the raw request path, without decoding percent-encoding, while the router decodes parameters when it resolves a route. A request whose path is percent-encoded can therefore resolve to a page while failing to match the route rule meant to protect it, so the rule's `appMiddleware` never runs, including during server rendering.

For a page served through a dynamic or catch-all route, an attacker can percent-encode a character in the path to skip the rule:
CVSS 6.5 (version 3.1; evidence as of Oct 22, 2026; https://github.com/advisories/GHSA-6gq8-jgmh-3ffp).
EPSS 0.4% for the following 30 days, scored Oct 26, 2026 (https://api.first.org/data/v1/epss?cve=CVE-2026-114131&date=2026-10-26).
Sources:
GitHub-reviewed advisory GHSA-6gq8-jgmh-3ffp: https://github.com/advisories/GHSA-6gq8-jgmh-3ffp
GitHub public advisory API page: https://api.github.com/advisories?type=reviewed&per_page=100&sort=updated&direction=desc&after=Y3Vyc29yOnYyOpK0MjAyNi0xMC0yM1QyMDo1MTozMFrOAAf0Mg%3D%3D
GitHub public advisory API page: https://api.github.com/advisories?type=reviewed&per_page=100&sort=updated&direction=desc&after=Y3Vyc29yOnYyOpK0MjAyNi0xMC0yM1QyMDo0OToxMlrOAAf0LQ%3D%3D
GitHub public advisory API page: https://api.github.com/advisories?type=reviewed&per_page=100&sort=updated&direction=desc&after=Y3Vyc29yOnYyOpK0MjAyNi0xMC0yM1QyMDo0NzoxN1rOAAf0Kg%3D%3D
GitHub public advisory API page: https://api.github.com/advisories?type=reviewed&per_page=100&sort=updated&direction=desc&after=Y3Vyc29yOnYyOpK0MjAyNi0xMC0yM1QyMDo0NTozNlrOAAf0Jw%3D%3D
GitHub public advisory API page: https://api.github.com/advisories?type=reviewed&per_page=100&sort=updated&direction=desc&after=Y3Vyc29yOnYyOpK0MjAyNi0xMC0yM1QyMDo0NTowNVrOAAf0JQ%3D%3D
GitHub public advisory API page: https://api.github.com/advisories?type=reviewed&per_page=100&sort=updated&direction=desc&after=Y3Vyc29yOnYyOpK0MjAyNi0xMC0yM1QyMDo0Mzo0NVrOAAf0Iw%3D%3D
GitHub public advisory API page: https://api.github.com/advisories?type=reviewed&per_page=100&sort=updated&direction=desc&after=Y3Vyc29yOnYyOpK0MjAyNi0xMC0yM1QyMDo0MzozMVrOAAf0Ig%3D%3D
GitHub public advisory API page: https://api.github.com/advisories?type=reviewed&per_page=100&sort=updated&direction=desc&after=Y3Vyc29yOnYyOpK0MjAyNi0xMC0yM1QxODozNTowMVrOAAZRcw%3D%3D
GitHub public advisory API page: https://api.github.com/advisories?type=reviewed&per_page=100&sort=updated&direction=desc&after=Y3Vyc29yOnYyOpK0MjAyNi0xMC0yM1QxODozMDoyN1rOAAY_5Q%3D%3D
GitHub public advisory API page: https://api.github.com/advisories?type=reviewed&per_page=100&sort=updated&direction=desc&after=Y3Vyc29yOnYyOpK0MjAyNi0xMC0yM1QxODoyOTowNVrOAAfz8g%3D%3D
FIRST measured EPSS score: https://api.first.org/data/v1/epss?cve=CVE-2026-114131&date=2026-10-26
Record ID: CVE-2026-114131.
Record origin: Ingested record.
AI evidence: Not assessed.
Known exploitation: Not assessed.
Zero-day status: Not assessed. KEV membership alone does not establish zero-day status.
About this data

This record was ingested from a data source. Retrieved: Oct 27, 2026, 01:40 UTC. Ingestion is not an independent editorial investigation.

A CISA KEV listing documents known exploitation, not necessarily a zero-day; absence from the catalog does not prove a vulnerability has never been exploited.

Technology tags indicate possible relevance, not verified exposure. Confirm the affected product, version, and configuration against your own inventory; KEVWire does not scan your systems.

A personal reading checklist on this device, not verified remediation.

Record JSON

Your account

Email alerts

Email alerts are not available yet. To follow your stack today, use its RSS feed, which honors your filters, or connect an AI agent through the API.

Suggest an improvement

Ideas, missing sources, corrections, and bugs are all welcome. No account needed. Suggestions are reviewed by a person before anything changes.

Record details

Record detail