free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF terminates the entire process when a stored PFD-subscription notifyUri cannot be reached. In PfdChangeNotifier.FlushNotifications(), the notifier calls NnefPFDmanagementNotify(...) and on any delivery error invokes logger.PFDManageLog.Fatal(err), which is os.Exit(1)-equivalent in Go. An attacker who can create a PFD subscription with an attacker-chosen notifyUri and then trigger a PFD change can deterministically kill NEF on the asynchronous delivery attempt -- the process exits with status 1, dropping NEF's entire SBI surface until restart. This vulnerability is fixed in 4.2.2.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NRF root SBI endpoint POST /oauth2/token contains a parser-level type-confusion bug family. The handler in NFs/nrf/internal/sbi/api_accesstoken.go reflects over models.NrfAccessTokenAccessTokenReq, special-cases only plain string and NrfNfManagementNfType fields, and treats every other field as if it were a single models.PlmnId. The parsed *models.PlmnId is then assigned with reflect.Value.Set() to whichever field name the attacker put in the form body, which panics whenever the destination field's real type is incompatible (slice, different struct, primitive). Gin recovery converts each panic into HTTP 500, but the endpoint remains remotely panicable from a single unauthenticated form-encoded request and is repeatedly triggerable. This vulnerability is fixed in 4.2.2.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF PATCH /3gpp-pfd-management/v1/{afId}/transactions/{transId}/applications/{appId} handler panics with a nil-pointer dereference when the upstream UDR call fails AND the consumer wrapper returns err != nil together with a nil *ProblemDetails. The handler's errPfdData != nil branch builds its own problemDetailsErr correctly, but immediately after it reads problemDetails.Cause (the OTHER value, which is nil in this branch) and panics. Gin recovery converts the panic into HTTP 500, so a single PATCH against this endpoint returns 500 instead of the intended controlled error response whenever UDR access is failing. This vulnerability is fixed in 4.2.2.

free5GC UDR is the Policy Control Function (PCF) for free5GC, an an open-source project for 5th generation (5G) mobile core networks. A memory leak vulnerability in versions prior to 1.4.3 allows any unauthenticated attacker with network access to the PCF SBI interface to cause uncontrolled memory growth by sending repeated HTTP requests to the OAM endpoint. The root cause is a `router.Use()` call inside an HTTP handler that registers a new CORS middleware on every incoming request, permanently growing the Gin router's handler chain. This leads to progressive memory exhaustion and eventual Denial of Service of the PCF, preventing all UEs from obtaining AM and SM policies and blocking 5G session establishment. Version 1.4.3 contains a patch.

free5GC is an open source 5G core network. free5GC NRF prior to version 1.4.2 has an Improper Input Validation vulnerability leading to Denial of Service. All deployments of free5GC using the NRF discovery service are affected. The `EncodeGroupId` function attempts to access array indices [0], [1], [2] without validating the length of the split data. When the parameter contains insufficient separator characters, the code panics with "index out of range". A remote attacker can cause the NRF service to panic and crash by sending a crafted HTTP GET request with a malformed `group-id-list` parameter. This results in complete denial of service for the NRF discovery service. free5GC NRF version 1.4.2 fixes the issue. There is no direct workaround at the application level. The recommendation is to apply the provided patch or restrict access to the NRF API to trusted sources only.

free5GC is an open source 5G core network. free5GC AUSF prior to version 1.4.2 has is an Improper Null Check vulnerability leading to Denial of Service. All deployments of free5GC v4.0.1 using the AUSF UE authentication service (`/nausf-auth/v1/ue-authentications` endpoint) are affected. A remote attacker can cause the AUSF service to panic and crash by sending a crafted UE authentication request that triggers a nil interface conversion in the `GetSupiFromSuciSupiMap` function. This results in complete denial of service for the AUSF authentication service. The `GetSupiFromSuciSupiMap` function attempts to perform an interface conversion from `interface{}` to `*context.SuciSupiMap` without checking if the underlying value is nil. When `SuciSupiMap` is nil, the code panics with "interface conversion: interface {} is nil, not *context.SuciSupiMap". free5GC AUSF version 1.4.2 patches the issue. There is no direct workaround at the application level. The recommendation is to apply the provided patch or restrict access to the AUSF API to trusted sources only.

An issue in Free5GC v.4.2.0 and before allows a remote attacker to cause a denial of service via the function HandleAuthenticationFailure of the component AMF

free5GC SMF provides Session Management Function for free5GC, an open-source project for 5th generation (5G) mobile core networks. In versions up to and including 1.4.1, SMF panics and terminates when processing a malformed PFCP SessionReportRequest on the PFCP (UDP/8805) interface. No known upstream fix is available, but some workarounds are available. ACL/firewall the PFCP interface so only trusted UPF IPs can reach SMF (reduce spoofing/abuse surface); drop/inspect malformed PFCP SessionReportRequest messages at the network edge where feasible, and/or add recover() around PFCP handler dispatch to avoid whole-process termination (mitigation only).

A vulnerability has been found in Free5GC up to 4.1.0. This affects an unknown function of the component PFCP UDP Endpoint. Such manipulation leads to denial of service. The attack can be launched remotely. The exploit has been disclosed to the public and may be used.

A flaw has been found in Free5GC SMF up to 4.1.0. Affected is the function HandlePfcpAssociationReleaseRequest of the file internal/pfcp/handler/handler.go of the component PFCP UDP Endpoint. Executing a manipulation can lead to null pointer dereference. The attack may be launched remotely. The exploit has been published and may be used. A patch should be applied to remediate this issue.

A weakness has been identified in Free5GC up to 4.1.0. Affected is the function SessionDeletionResponse of the component SMF. This manipulation causes null pointer dereference. The attack is possible to be carried out remotely. The exploit has been made available to the public and could be used for attacks. It is suggested to install a patch to address this issue.

A vulnerability has been found in Free5GC SMF up to 4.1.0. Affected by this vulnerability is the function HandlePfcpSessionReportRequest of the file internal/pfcp/handler/handler.go of the component PFCP. The manipulation leads to denial of service. Remote exploitation of the attack is possible. The exploit has been disclosed to the public and may be used. To fix this issue, it is recommended to deploy a patch.

A security flaw has been discovered in Free5GC up to 4.1.0. This impacts the function identityTriggerType of the file pfcp_reports.go. The manipulation results in null pointer dereference. The attack can be executed remotely. The exploit has been released to the public and may be used for attacks. Applying a patch is advised to resolve this issue.

free5gc UDM provides Unified Data Management (UDM) for free5GC, an open-source project for 5th generation (5G) mobile core networks. Versions up to and including 1.4.1 have a NULL Pointer Dereference vulnerability. Remote unauthenticated attackers can trigger a service panic (Denial of Service) by sending a crafted PUT request with an unexpected ueId, crashing the UDM service. All deployments of free5GC using the UDM component may be affected. free5gc/udm pull request 76 contains a fix for the issue. No direct workaround is available at the application level. Applying the official patch is recommended.

free5GC is an open-source project for 5th generation (5G) mobile core networks. free5GC go-upf versions up to and including 1.2.6, corresponding to free5gc smf up to and including 1.4.0, have an Improper Input Validation and Protocol Compliance vulnerability leading to Denial of Service. Remote attackers can disrupt core network functionality by sending a malformed PFCP Association Setup Request. The UPF incorrectly accepts it, entering an inconsistent state that causes subsequent legitimate requests to trigger SMF reconnection loops and service degradation. All deployments of free5GC using the UPF and SMF components may be affected. As of time of publication, a fix is in development but not yet available. No direct workaround is available at the application level. Applying the official patch, once released, is recommended.

The free5GC UPF suffers from a lack of bounds checking on the SEID when processing PFCP Session Deletion Requests. An unauthenticated remote attacker can send a request with a very large SEID (e.g., 0xFFFFFFFFFFFFFFFF) that causes an integer conversion/underflow in LocalNode.DeleteSess() / LocalNode.Sess() when a uint64 SEID is converted to int and used in index arithmetic. This leads to a negative index into n.sess and a Go runtime panic, resulting in a denial of service (UPF crash). The issue has been reproduced on free5GC v4.1.0 with crashes observed in the session lookup/deletion path in internal/pfcp/node.go; other versions may also be affected. No authentication is required.

Free5gc 4.0.1 is vulnerable to Buffer Overflow. The AMF incorrectly validates the 5GS mobile identity, resulting in slice reference overflow.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's PCF POST /npcf-smpolicycontrol/v1/sm-policies handler (HandleCreateSmPolicyRequest) panics with a nil-pointer dereference when a downstream OpenAPI consumer call (UDR lookup) returns 404 Not Found and the consumer wrapper returns err != nil together with a nil response struct. The handler logs the OpenAPI error and continues executing instead of returning, then dereferences the nil response struct on a subsequent line and panics. Gin recovery converts the panic into HTTP 500, so a single attacker-shaped POST returns 500 instead of a clean 4xx whenever the downstream lookup fails. The PCF process keeps running. The trigger is a single POST containing input that causes the downstream UDR lookup to fail (e.g. an unknown DNN). In 4.2.1 this endpoint is also reachable WITHOUT an Authorization header because the PCF Npcf_SMPolicyControl route group is mounted without inbound auth middleware. This vulnerability is fixed in 4.2.2.

Free5GC is an open-source Linux Foundation project for 5th generation (5G) mobile core networks. Versions prior to 1.4.2 are vulnerable to procedure panic caused by Nil Pointer Dereference in the /sdm-subscriptions endpoint. A remote attacker can cause the UDM service to panic and crash by sending a crafted POST request to the /sdm-subscriptions endpoint with a malformed URL path containing path traversal sequences (../) and a large JSON payload. The DataChangeNotificationProcedure function in notifier.go attempts to access a nil pointer without proper validation, causing a complete service crash with "runtime error: invalid memory address or nil pointer dereference". Exploitation would result in UDM functionality disruption until recovery by restart. This issue has been fixed in version 1.4.2.

In Free5gc v3.0.5, the AMF breaks due to malformed NAS messages.

free5GC is an open-source project for 5th generation (5G) mobile core networks. Versions up to and including 1.4.1 of free5GC's AMF service have a Buffer Overflow vulnerability leading to Denial of Service. Remote unauthenticated attackers can crash the AMF service by sending a specially crafted NAS Registration Request with a malformed 5GS Mobile Identity, causing complete denial of service for the 5G core network. All deployments of free5GC using the AMF component may be affected. Pull request 43 of the free5gc/nas repo contains a fix. No direct workaround is available at the application level. Applying the official patch is recommended.

Null pointer dereference in free5gc pcf 1.4.0 in file internal/sbi/processor/ampolicy.go in function HandleDeletePoliciesPolAssoId.

An issue was discovered in function LocalNode.Sess in free5GC 4.1.0 allowing attackers to cause a denial of service or other unspecified impacts via crafted header Local SEID to the PFCP Session Modification Request.

An issue was discovered in Free5GC v4.0.0 and v4.0.1 allowing an attacker to cause a denial of service via crafted POST request to the Nnssf_NSSAIAvailability API.

free5GC SMF provides Session Management Function for free5GC, an open-source project for 5th generation (5G) mobile core networks. In versions up to and including 1.4.1, SMF panics and terminates when processing a malformed PFCP SessionReportRequest on the PFCP (UDP/8805) interface. No known upstream fix is available, but some workarounds are available. ACL/firewall the PFCP interface so only trusted UPF IPs can reach SMF (reduce spoofing/abuse surface); drop/inspect malformed PFCP SessionReportRequest messages at the network edge where feasible, and/or add recover() around PFCP handler dispatch to avoid whole-process termination (mitigation only).

free5GC SMF provides Session Management Function for free5GC, an open-source project for 5th generation (5G) mobile core networks. In versions up to and including 1.4.1, SMF panics due to nil pointer dereference and the SMF process terminates. This is triggered by a malformed PFCP SessionReportRequest on the SMF PFCP (UDP/8805) interface. No known upstream fix is available, but some workarounds are available. ACL/firewall the PFCP interface so only trusted UPF IPs can reach SMF (reduce spoofing/abuse surface); drop/inspect malformed PFCP SessionReportRequest messages at the network edge where feasible, and/or add recover() around PFCP handler dispatch to avoid whole-process termination (mitigation only).

A vulnerability was determined in Free5GC up to 4.1.0. The impacted element is the function establishPfcpSession of the component SMF. Executing a manipulation can lead to null pointer dereference. The attack may be launched remotely. The exploit has been publicly disclosed and may be utilized. It is best practice to apply a patch to resolve this issue.

A vulnerability was found in Free5GC SMF up to 4.1.0. Affected by this issue is the function HandleReports of the file /internal/context/pfcp_reports.go of the component PFCP UDP Endpoint. The manipulation results in denial of service. The attack can be executed remotely. It is advisable to implement a patch to correct this issue.

A vulnerability has been found in Free5GC pcf up to 1.4.1. This affects the function HandleCreateSmPolicyRequest of the file internal/sbi/processor/smpolicy.go. The manipulation leads to null pointer dereference. The attack is possible to be carried out remotely. The exploit has been disclosed to the public and may be used. The identifier of the patch is df535f5524314620715e842baf9723efbeb481a7. Applying a patch is the recommended action to fix this issue.

A vulnerability was identified in Free5GC up to 4.1.0. This affects the function ResolveNodeIdToIp of the file internal/sbi/processor/datapath.go of the component SMF. The manipulation leads to denial of service. Remote exploitation of the attack is possible. The exploit is publicly available and might be used. It is recommended to apply a patch to fix this issue.

An array index out of bounds vulnerability in the AMF component of free5GC v4.0.1 allows remote attackers to cause a denial of service via a crafted 5GS Mobile Identity in a NAS Registration Request message. The issue occurs in the GetSUCI method (NAS_MobileIdentity5GS.go) when accessing index 5 of a 5-element array, leading to a runtime panic and AMF crash.

A heap buffer overflow vulnerability in the UPF component of free5GC v4.0.1 allows remote attackers to cause a denial of service via a crafted PFCP Session Modification Request. The issue occurs in the SDFFilterFields.UnmarshalBinary function (sdf-filter.go) when processing a declared length that exceeds the actual buffer capacity, leading to a runtime panic and UPF crash.

free5GC go-upf is the User Plane Function (UPF) implementation for 5G networks that is part of the free5GC project. Versions prior to 1.2.8 have a Heap-based Buffer Overflow (CWE-122) vulnerability leading to Denial of Service. Remote attackers can crash the UPF network element by sending a specially crafted PFCP Session Modification Request with an invalid SDF Filter length field. This causes a heap buffer overflow, resulting in complete service disruption for all connected UEs and potential cascading failures affecting the SMF. All deployments of free5GC using the UPF component may be affected. Version 1.2.8 of go-upf contains a fix.

free5gc v4.1.0 and before is vulnerable to Buffer Overflow. When AMF receives an UplinkRANConfigurationTransfer NGAP message from a gNB, the AMF process crashes.

Buffer Overflow vulnerability in free5gc 3.3.0, UPF 1.2.0, and SMF 1.2.0 allows attackers to cause a denial of service via crafted PFCP messages.

Buffer Overflow vulnerability in free5gc 3.3.0 allows attackers to cause a denial of service via crafted PFCP message with malformed PFCP Heartbeat message whose Recovery Time Stamp IE length is mutated to zero.

An issue was discovered in free5GC version 3.3.0, allows remote attackers to execute arbitrary code and cause a denial of service (DoS) on AMF component via crafted NGAP message.

Buffer Overflow vulnerability in free5gc 3.3.0 allows attackers to cause a denial of service via crafted PFCP messages whose Sequence Number is mutated to overflow bytes.

An improper input validation and protocol compliance vulnerability in free5GC v4.0.1 allows remote attackers to cause a denial of service. The UPF incorrectly accepts a malformed PFCP Association Setup Request, violating 3GPP TS 29.244. This places the UPF in an inconsistent state where a subsequent valid PFCP Session Establishment Request triggers a cascading failure, disrupting the SMF connection and causing service degradation.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the nnef-callback route group without inbound OAuth2/bearer-token authorization. A forged or arbitrary bearer token (e.g. Authorization: Bearer not-a-real-token) is enough to reach the SMF-callback handler -- the callback body is parsed and dispatched into NEF business logic instead of being rejected at the auth boundary. Same root cause as the other NEF SBI findings: the route group is mounted without any inbound auth middleware. NEF does not authenticate the producer NF identity before processing callback content; if an attacker can guess or obtain a valid NotifId, this missing auth boundary lets forged callbacks act on real subscription state. The route group is also reachable even when the runtime ServiceList does not declare it (it lists only nnef-pfdmanagement and nnef-oam). This vulnerability is fixed in 4.2.2.

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.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the nnef-oam route group without inbound OAuth2/bearer-token authorization. A network attacker who can reach NEF on the SBI can hit the OAM route with no Authorization header at all and the handler returns 200 OK. The current OAM handler is a stub that returns null, but the structural defect is route-group-scoped: the entire OAM route group has no inbound auth middleware, so every future OAM operation added to this group inherits the missing auth boundary by default. This vulnerability is fixed in 4.2.2.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, PCF Npcf_SMPolicyControl missing authentication middleware allows unauthenticated access to SM policy handlers and disclosure of subscriber SUPI. In NewServer(), the smPolicyGroup route group is created and routes are applied without attaching the router authorization middleware. In contrast, other PCF service groups such as Npcf_PolicyAuthorization do attach RouterAuthorizationCheck before route registration. Because the middleware is missing, requests to the /npcf-smpolicycontrol/v1/sm-policies, /npcf-smpolicycontrol/v1/sm-policies/{smPolicyId}, /npcf-smpolicycontrol/v1/sm-policies/{smPolicyId}/update, and /npcf-smpolicycontrol/v1/sm-policies/{smPolicyId}/delete endpoints can reach business logic even when no valid OAuth token is provided. This vulnerability is fixed in 4.2.2.

Free5gc v3.2.1 is vulnerable to Information disclosure.

An issue was discovered in Free5GC v4.0.0 and v4.0.1 allowing an attacker to cause a denial of service via crafted POST request to the Npcf_BDTPolicyControl API.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's SMF mounts the UPI management route group without OAuth2/bearer-token authorization middleware. A network attacker who can reach SMF on the SBI can hit UPI endpoints with no Authorization header at all, and the requests reach the SMF business handlers. In the running Docker lab this was directly demonstrated for read (GET /upi/v1/upNodesLinks), write (POST /upi/v1/upNodesLinks with attacker-controlled UP-node and link payload), and delete (DELETE /upi/v1/upNodesLinks/{nodeID}) operations. This vulnerability is fixed in 4.2.2.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the 3gpp-traffic-influence API without inbound OAuth2/bearer-token authorization. A network attacker who can reach NEF on the SBI can create, read, patch, and delete traffic-influence subscriptions either with no Authorization header at all, or with a forged bearer token (e.g. Authorization: Bearer not-a-real-token). This includes creating AnyUeInd=true subscriptions intended to affect group / any-UE traffic steering. 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.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's SMF mounts the UPI management route group without inbound OAuth2 middleware. On top of that, the DELETE /upi/v1/upNodesLinks/{upNodeRef} handler unconditionally dereferences upNode.UPF after the type-guarded async release, even though AN-typed nodes are constructed without a UPF object. As a result, a single unauthenticated DELETE /upi/v1/upNodesLinks/gNB1 request crashes the handler with a nil-pointer panic AND mutates the in-memory user-plane topology before panicking (the UpNodeDelete(upNodeRef) line runs first). This is an unauthenticated, state-mutating panic-DoS sink that an off-path network attacker can trigger by name against any AN entry. This vulnerability is fixed in 4.2.2.

Transient DOS while processing DL NAS Transport message, as specified in 3GPP 24.501 v16.