CVE-2026-118489
HIGH
MEDIUM
Priority: 0.03
BB Relevance:
75/100
Published: 2026-11-03
Modified: 2026-11-03
First seen: 2026-11-03
Status: active
Attack Surface
Network
Low Complexity
No Auth
No Interaction
Conf. Impact
CVSS Vector Breakdown
AV:
Network
AC:
Low
PR:
None
UI:
None
S:
Unchanged
C:
High
I:
None
A:
None
Description
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.
Weakness Classification (2)
Affected Software (4)
| Vendor | Product | Version |
|---|---|---|
| Eclipse Foundation | Eclipse Vert.x | 4.0.0 |
| Eclipse Foundation | Eclipse Vert.x | 5.0.0 |
| Eclipse Foundation | Eclipse Vert.x | 4.0.0 |
| Eclipse Foundation | Eclipse Vert.x | 5.0.0 |