CVE-2026-33804

critical

Published 2026-04-16 · Modified 2026-04-16

💬 Discuss on Community ✚ Propose mitigation

CVSS v3

9.1

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

CVSS v4 NEW

—

not yet in upstream

VIR risk

9.1

Description

@fastify/middie vulnerable to middleware bypass via deprecated ignoreDuplicateSlashes option

Predictions

Exploit likelihood

94%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

Package impact

Ecosystem	Package	Vulnerable	Fixed
npm	@fastify/middie	`<9.3.2`	`9.3.2`

Application impact

Vendor	Product	Versions	Fixed
fastify	fastify\/middie	`{"endExcluding":"9.3.2"}`	`9.3.2`

References

CWEs

CWE-436

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.