CVE-2026-1002CWE-444

Eclipse Vert.x Web static handler file access denial

Medium · published January 15, 2026

CVSS v4.0
6.9
EPSS
0%
Percentile
31.2
In the wild
Unconfirmed
What it is

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);

The record
Technical detail
CVSS v4.0
6.9 · MEDIUM
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
EPSS
0.00384 · 31.2th percentile
Weakness
CWE-444 · Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
Published
2026-01-15T20:50Z
EPSS history
Timeline
  • 15 JAN 20:50Z
    Eclipse Vert.x Web static handler file access denial
    cvelistv5