CVE-2021-27306

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-03-18 · updated 2026-06-17
Weakness: CWE-706

Description

An improper access control vulnerability in the JWT plugin in Kong Gateway prior to 2.3.2.0 allows unauthenticated users access to authenticated routes without a valid token JWT.

Affected products

KongHQ Kong Gateway: before 2.3.2.0 — fixed in 2.3.2.0

How to fix

Upgrade to a fixed version: KongHQ Kong Gateway 2.3.2.0. Check the vendor advisory for mitigations.

References

https://docs.konghq.com/enterprise/changelog/#core-1
https://medium.com/%40sew.campos/cve-2021-27306-access-an-authenticated-route-on-kong-api-gateway-6ae3d81968a3
https://docs.konghq.com/enterprise/changelog/#core-1
https://medium.com/%40sew.campos/cve-2021-27306-access-an-authenticated-route-on-kong-api-gateway-6ae3d81968a3

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