Vulnerability-Lookup

CVE-2026-85184 (GCVE-0-2026-85184)

Vulnerability from cvelistv5 – Published: 2026-09-04 09:15 – Updated: 2026-09-04 19:36

Title

@fastify/middie vulnerable to path-scoped middleware bypass via absolute-form request target

Summary

@fastify/middie versions >= 9.1.0 and before 9.3.4 decide whether to run path-scoped middleware by matching against the raw request target, while the Fastify router resolves an absolute-form request target to its path before dispatching. Because the two layers evaluate different strings, a request using an absolute-form target reaches the route handler while the path-scoped middleware, such as authentication or authorization, is skipped. An unauthenticated network attacker can use this to bypass path-based access controls in a Fastify application that relies on middie for those controls. Users should upgrade to @fastify/middie 9.3.4 or later.

Severity

9.1 (Critical)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-04 19:36 UTC

CWE

CWE-436 - Interpretation Conflict

Assigner

openjs redhat root

References

2 references

URL	Tags
https://github.com/fastify/middie/security/adviso…
https://cna.openjsf.org/security-advisories.html

Impacted products

1 product

Vendor	Product	Version	CPE status
@fastify/middie	@fastify/middie	Affected: 9.1.0 , < 9.3.4 (semver) Unaffected: 9.3.4 (semver)	guessed

Credits

zer0d4y5 mcollina UlisesGascon

Show details on NVD website

JSON

To clipboard

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FKIE_CVE-2026-85184

Vulnerability from fkie_nvd - Published: 2026-09-04 10:17 - Updated: 2026-09-04 20:17

Severity

9.1 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Summary

References

	URL	Tags
	ce714d77-add3-4f53-aff5-83d477b104bb	https://cna.openjsf.org/security-advisories.html
	ce714d77-add3-4f53-aff5-83d477b104bb	https://github.com/fastify/middie/security/advisories/GHSA-hx87-8wv7-pjv8

Impacted products

	Vendor	Product	Version

JSON

To clipboard

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          "defaultStatus": "unaffected",
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  ],
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        "impactScore": 5.2,
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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

CVE-2026-85184 (GCVE-0-2026-85184)

FKIE_CVE-2026-85184

Tags

Sightings

Nomenclature