Skip to main content

CVE detail

CVE-2026-6556

@fastify/express versions 4.0.6 and earlier only rewrite the plugin prefix for middleware mount paths when the path argument is a string. Non-string mount paths (arrays of paths and regular expressions) are left unprefixed inside prefixed plugin scopes, so middleware registered with those forms does not match the actual prefixed request path. Applications that use path-scoped middleware for authentication, authorization, rate limiting, or auditing on routes inside a prefixed scope can be bypassed by sending a request to the prefixed route, because Fastify still matches the route but the middleware is skipped. Patches: upgrade to @fastify/express 4.0.7. Workarounds: use string mount paths instead of arrays or regular expressions in prefixed plugins, or register one use call per path.

CVSS 9.1 · CriticalBuzz score 21.0

Buzz score

Why this CVE is surfacing

Buzz score total 21.0

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
Mention score
11.0
2 evidence mentions in the snapshot
Diversity score
10.0
2 sources across 2 categories
KEV score
0.0
No KEV entry observed
OTX score
0.0
0 OTX pulses
PoC score
0.0
0 repos · best confidence N/A
Best PoC traction
0
Maximum stars on a matched PoC repo

Why it matters now

Mention timeline

Total mentions
2
within the 30d window
Peak daily
2
highest bucket

Evidence

Source links by recency

Newest mentions first
2 source links · newest first

Exploit code

Public exploit repository references

Public PoC repositories are third-party, potentially unsafe artifacts. Treat their code as untrusted and use it only on authorized systems in an isolated, least-privilege environment. cvebuzz does not execute the code or verify that an exploit works.

0 repository references · best confidence N/A · max 0 stars
No public PoC repositories have been matched yet.

Related records

Similar CVEs

6 related CVEs with shared weakness or product evidence
  • CVE-2026-18207

    A flaw was found in the client policy enforcement mechanism of Keycloak. The issue occurs when the system checks group membership by name instead of a unique identifier. An attack…

    CVSS 6.5 · Medium
    1 mention
  • CVE-2026-47726

    nebula-mesh is a self-hosted control plane for Slack Nebula mesh virtual private network. Prior to version 0.3.2, internal/api/audit.go:12 — handleGetAuditLog does no admin check.…

    CVSS 7.1 · High
    3 mentions
  • CVE-2026-61487

    Improper Authorization vulnerability in Apache ActiveMQ Broker, Apache ActiveMQ All, Apache ActiveMQ. An authenticated low-privilege user can bypass a per-destination write ACL…

    CVSS 6.5 · Medium
    2 mentions
  • CVE-2026-64743

    An authorization issue was addressed with improved state management. This issue is fixed in iOS 26.6 and iPadOS 26.6, macOS Tahoe 26.6, tvOS 26.6, visionOS 26.6, watchOS 26.6. An…

    CVSS 6.5 · Medium
    5 mentions
  • CVE-2026-64711

    This issue was addressed with additional entitlement checks. This issue is fixed in iOS 26.6 and iPadOS 26.6, macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, macOS Tahoe 26.6. An app m…

    CVSS 5.5 · Medium
    4 mentions
  • CVE-2026-43792

    An authorization issue was addressed with improved state management. This issue is fixed in Safari 26.6, macOS Tahoe 26.6. An app may be able to access sensitive user data.

    CVSS 6.5 · Medium
    2 mentions