Vulnerability-Lookup

CVE-2026-92087 (GCVE-0-2026-92087)

Vulnerability from cvelistv5 – Published: 2026-09-16 14:21 – Updated: 2026-09-16 14:21

Title

@fastify/auth vulnerable to Authorization Bypass via order-dependent evaluation of composed auth

Summary

@fastify/auth is a Fastify plugin that composes multiple authentication and authorization strategies into a single route guard. In versions 5.0.0 through 5.1.0, when strategies are composed with the relation "or" option together with the run "all" option and one entry is a nested array acting as an AND group, the group is evaluated in an order-dependent way: an earlier failing check is silently dropped and the group's result becomes the outcome of its last check. As a result, a request that satisfies only the last member of an AND group, for example an attacker who holds a valid API key but is not an administrator, is authorized instead of rejected, and a related order-dependent bypass affects the mirror configuration where the top-level relation is "and" and a nested group uses "or". The issue is fixed in @fastify/auth 5.1.1, and users should upgrade to 5.1.1 or later. As a workaround, omit the run "all" option where it is not required, order each AND group so its stricter check is evaluated last, or replace nested AND groups with an explicit top-level "and" composition.

Severity

8.1 (High)


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

CWE

CWE-285 - Improper Authorization
CWE-697 - Incorrect Comparison

Assigner

openjs redhat root

References

2 references

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

Impacted products

1 product

Vendor	Product	Version	CPE status
@fastify/auth	@fastify/auth	Affected: 5.0.0 , < 5.1.1 (semver) Unaffected: 5.1.1 (semver)	guessed

Credits

Sengtocxoen UlisesGascon mcollina

Show details on NVD website

JSON

To clipboard

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    "datePublished": "2026-09-16T14:21:23.686Z",
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FKIE_CVE-2026-92087

Vulnerability from fkie_nvd - Published: 2026-09-16 15:18 - Updated: 2026-09-16 19:40

Severity

8.1 (High) - CVSS:3.1/AV:N/AC:L/PR:L/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/fastify-auth/security/advisories/GHSA-7h52-2rwr-m76r

Impacted products

	Vendor	Product	Version

JSON

To clipboard

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  "lastModified": "2026-09-16T19:40:00.317",
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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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.