CVE detail
CVE-2026-33804
@fastify/middie versions 9.3.1 and earlier are vulnerable to middleware bypass when the deprecated Fastify ignoreDuplicateSlashes option is enabled. The middleware path matching logic does not account for duplicate slash normalization performed by Fastify's router, allowing requests with duplicate slashes to bypass middleware authentication and authorization checks. This only affects applications using the deprecated ignoreDuplicateSlashes option. Upgrade to @fastify/middie 9.3.2 to fix this issue. There are no workarounds other than disabling the ignoreDuplicateSlashes option.
Buzz score
Why this CVE is surfacing
This all-time snapshot uses the same composite formula as Trending across a 30-year evidence window, rather than a current rolling window.
Buzz score components · mention 11.0 · diversity 10.0 · KEV 0.0 · OTX 0.0 · PoC 0.0
Why it matters now
Mention timeline
- Total mentions
- 0
- within the 30d window
- Peak daily
- 0
- highest bucket
Evidence
Source links by recency
2 source links · newest first
No excerpt available.
Exploitgithub.comApr 16, 2026, 3:17 PM- https://cna.openjsf.org/security-advisories.htmlcna.openjsf.org
No excerpt available.
Vendor Advisorycna.openjsf.orgApr 16, 2026, 3:17 PM
Exploit code
Public exploit repository references
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0 repository references · best confidence N/A · max 0 stars
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