CVE-2026-118489
CachingWebClient shares user-specific HTTP responses across users via the shared cache tier
In Eclipse Vert.x versions [4.0.0,4.5.35] or [5.0.0,5.2.2], when one `CachingWebClient` is shared across users — the documented pattern of a per-user `WebClientSession` over a shared caching client — a response that is specific to one user but is cacheable and not marked `private`/`no-store` is stored in the client-level shared cache tier and served to other users requesting the same URL. A later user's session, or an anonymous caller through the same client, can receive an earlier user's response. Depending on the response this discloses authenticated content or a session cookie, the latter enabling session fixation or hijacking.
| CWE | CWE-200 CWE-524 |
| Vendor | eclipse foundation |
| Product | eclipse vert.x |
| Published | Nov 3, 2026 |
Get instant alerts for eclipse foundation eclipse vert.x
Be the first to know when new high vulnerabilities affecting eclipse foundation eclipse vert.x are published — delivered to Slack, Telegram or Discord.
CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N