vulnerability / NVI-00017515 / Revision 1
Centrifugo's dynamic JWKS key cache keyed only by `kid` allows cross-issuer JWT authentication bypass
GitHub lists this reviewed advisory for github.com/centrifugal/centrifugo/v6, github.com/centrifugal/centrifugo/v5, github.com/centrifugal/centrifugo/v4, github.com/centrifugal/centrifugo/v3, github.com/centrifugal/centrifugo. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.
This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.
01 / Meaning
Why it matters
Published affected context helps an owner decide what evidence to gather. This report has not examined your application.
8.2 high
GitHub source severity; exploitability and local consequence require separate evidence.
As of · GitHub Advisory Database
02 / Applicability
The affected context
Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.
github.com/centrifugal/centrifugo/v6
source listed<= 6.8.0
#### Summary Centrifugo's dynamic JWKS endpoint feature can verify a JWT for one allowed issuer using a public key cached from another allowed issuer. The JWKS cache and `singleflight` lookup are keyed only by the JWT header `kid`, not by the resolved JWKS endpoint, issuer, audience, or other trust-domain namespace. In a documented multi-issuer dynamic JWKS configuration, an attacker who can obtain or mint a valid token for issuer/tenant A can authenticate as issuer/tenant B if both JWKS documents use the same `kid` value and tenant A's key is cached first. This affects connection token verification and subscription token verification because both paths use the same JWKS verification manager. #### Details The vulnerable path is reachable when either of these shipped configuration options is set to a templated JWKS URL using values derived from JWT `iss` or `aud` claims: - `client.token.jwks_public_endpoint` - `client.subscription_token.jwks_public_endpoint` Relevant shipped config fields are defined in `internal/configtypes/types.go:59-65`, mapped into verifier configuration in `internal/confighelpers/jwt.go:36-41`, and exposed in the generated config schema at `internal/cli/
github.com/centrifugal/centrifugo/v5
source listed<= 5.4.9
#### Summary Centrifugo's dynamic JWKS endpoint feature can verify a JWT for one allowed issuer using a public key cached from another allowed issuer. The JWKS cache and `singleflight` lookup are keyed only by the JWT header `kid`, not by the resolved JWKS endpoint, issuer, audience, or other trust-domain namespace. In a documented multi-issuer dynamic JWKS configuration, an attacker who can obtain or mint a valid token for issuer/tenant A can authenticate as issuer/tenant B if both JWKS documents use the same `kid` value and tenant A's key is cached first. This affects connection token verification and subscription token verification because both paths use the same JWKS verification manager. #### Details The vulnerable path is reachable when either of these shipped configuration options is set to a templated JWKS URL using values derived from JWT `iss` or `aud` claims: - `client.token.jwks_public_endpoint` - `client.subscription_token.jwks_public_endpoint` Relevant shipped config fields are defined in `internal/configtypes/types.go:59-65`, mapped into verifier configuration in `internal/confighelpers/jwt.go:36-41`, and exposed in the generated config schema at `internal/cli/
github.com/centrifugal/centrifugo/v4
source listed<= 4.1.5
#### Summary Centrifugo's dynamic JWKS endpoint feature can verify a JWT for one allowed issuer using a public key cached from another allowed issuer. The JWKS cache and `singleflight` lookup are keyed only by the JWT header `kid`, not by the resolved JWKS endpoint, issuer, audience, or other trust-domain namespace. In a documented multi-issuer dynamic JWKS configuration, an attacker who can obtain or mint a valid token for issuer/tenant A can authenticate as issuer/tenant B if both JWKS documents use the same `kid` value and tenant A's key is cached first. This affects connection token verification and subscription token verification because both paths use the same JWKS verification manager. #### Details The vulnerable path is reachable when either of these shipped configuration options is set to a templated JWKS URL using values derived from JWT `iss` or `aud` claims: - `client.token.jwks_public_endpoint` - `client.subscription_token.jwks_public_endpoint` Relevant shipped config fields are defined in `internal/configtypes/types.go:59-65`, mapped into verifier configuration in `internal/confighelpers/jwt.go:36-41`, and exposed in the generated config schema at `internal/cli/
github.com/centrifugal/centrifugo/v3
source listed<= 3.2.3
#### Summary Centrifugo's dynamic JWKS endpoint feature can verify a JWT for one allowed issuer using a public key cached from another allowed issuer. The JWKS cache and `singleflight` lookup are keyed only by the JWT header `kid`, not by the resolved JWKS endpoint, issuer, audience, or other trust-domain namespace. In a documented multi-issuer dynamic JWKS configuration, an attacker who can obtain or mint a valid token for issuer/tenant A can authenticate as issuer/tenant B if both JWKS documents use the same `kid` value and tenant A's key is cached first. This affects connection token verification and subscription token verification because both paths use the same JWKS verification manager. #### Details The vulnerable path is reachable when either of these shipped configuration options is set to a templated JWKS URL using values derived from JWT `iss` or `aud` claims: - `client.token.jwks_public_endpoint` - `client.subscription_token.jwks_public_endpoint` Relevant shipped config fields are defined in `internal/configtypes/types.go:59-65`, mapped into verifier configuration in `internal/confighelpers/jwt.go:36-41`, and exposed in the generated config schema at `internal/cli/
github.com/centrifugal/centrifugo
source listed<= 2.4.0
#### Summary Centrifugo's dynamic JWKS endpoint feature can verify a JWT for one allowed issuer using a public key cached from another allowed issuer. The JWKS cache and `singleflight` lookup are keyed only by the JWT header `kid`, not by the resolved JWKS endpoint, issuer, audience, or other trust-domain namespace. In a documented multi-issuer dynamic JWKS configuration, an attacker who can obtain or mint a valid token for issuer/tenant A can authenticate as issuer/tenant B if both JWKS documents use the same `kid` value and tenant A's key is cached first. This affects connection token verification and subscription token verification because both paths use the same JWKS verification manager. #### Details The vulnerable path is reachable when either of these shipped configuration options is set to a templated JWKS URL using values derived from JWT `iss` or `aud` claims: - `client.token.jwks_public_endpoint` - `client.subscription_token.jwks_public_endpoint` Relevant shipped config fields are defined in `internal/configtypes/types.go:59-65`, mapped into verifier configuration in `internal/confighelpers/jwt.go:36-41`, and exposed in the generated config schema at `internal/cli/
03 / Response
What to do next
- investigate
Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database
A fixed release is not deployment evidence.
Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.
04 / Limits
What this report cannot establish
- Customer inventory, deployment, reachability and exploitation have not been inspected.
05 / Provenance
Sources you can inspect
Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.
- GHSA-g6vg-wj8f-48cj ↗
GitHub Advisory Database · vendor advisory
Observed . GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.
Public revision history
Only published revisions appear here. Routine fetches do not create a material-change event.
- Revision 1 ·
First indexed by Null; source disclosure date is shown separately.