Vulnerability-Lookup

GHSA-7G27-V5WJ-JR75

Vulnerability from github – Published: 2026-03-18 20:06 – Updated: 2026-03-20 21:24

Summary

free5GC UDM DataChangeNotification Procedure Panic Due to Nil Pointer Dereference

Details

Impact
This is a NULL Pointer Dereference vulnerability leading to Denial of Service.
- Security Impact: 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".
- Functional Impact: The service crashes completely, requiring manual restart. All UDM functionality is disrupted until recovery.
- Affected Parties: All deployments of free5GC v4.0.1 using the UDM HTTP callback functionality.

Patches
Yes, the issue has been patched.
The fix is implemented in PR free5gc/udm#78.
Users should upgrade to the next release of free5GC that includes this commit.

Workarounds
There is no direct workaround at the application level. The recommendation is to apply the provided patch or implement API gateway-level filtering to block requests containing path traversal sequences.

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/udm"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.4.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-33064"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-476",
      "CWE-478"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-03-18T20:06:36Z",
    "nvd_published_at": "2026-03-20T08:16:12Z",
    "severity": "HIGH"
  },
  "details": "**Impact**  \nThis is a NULL Pointer Dereference vulnerability leading to Denial of Service.  \n- **Security Impact**: 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\".  \n- **Functional Impact**: The service crashes completely, requiring manual restart. All UDM functionality is disrupted until recovery.  \n- **Affected Parties**: All deployments of free5GC v4.0.1 using the UDM HTTP callback functionality.\n\n**Patches**  \nYes, the issue has been patched.  \nThe fix is implemented in PR free5gc/udm#78.  \nUsers should upgrade to the next release of free5GC that includes this commit.\n\n**Workarounds**  \nThere is no direct workaround at the application level. The recommendation is to apply the provided patch or implement API gateway-level filtering to block requests containing path traversal sequences.",
  "id": "GHSA-7g27-v5wj-jr75",
  "modified": "2026-03-20T21:24:03Z",
  "published": "2026-03-18T20:06:36Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/free5gc/free5gc/security/advisories/GHSA-7g27-v5wj-jr75"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33064"
    },
    {
      "type": "WEB",
      "url": "https://github.com/free5gc/free5gc/issues/781"
    },
    {
      "type": "WEB",
      "url": "https://github.com/free5gc/udm/pull/78"
    },
    {
      "type": "WEB",
      "url": "https://github.com/free5gc/udm/commit/65d7070f4bfd016864cbbaefbd506bbc85d2fa92"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/free5gc/udm"
    }
  ],
  "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 UDM DataChangeNotification Procedure Panic Due to Nil Pointer Dereference"
}

CVE-2026-33064 (GCVE-0-2026-33064)

Vulnerability from cvelistv5 – Published: 2026-03-20 08:00 – Updated: 2026-03-20 15:42

Title

free5GC UDM DataChangeNotification Procedure Panic Due to Nil Pointer Dereference

Summary

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.

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-478 - Missing Default Case in Multiple Condition Expression

Assigner

GitHub_M

References

URL

Tags

	https://github.com/free5gc/free5gc/security/advis…	x_refsource_CONFIRM
	https://github.com/free5gc/free5gc/issues/781	x_refsource_MISC
	https://github.com/free5gc/udm/pull/78	x_refsource_MISC
	https://github.com/free5gc/udm/commit/65d7070f4bf…	x_refsource_MISC

Impacted products

	Vendor	Product	Version
	free5gc	free5gc	Affected: < 1.4.2

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-33064",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-03-20T15:42:37.002784Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-03-20T15:42:53.709Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "free5gc",
          "vendor": "free5gc",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 1.4.2"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "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."
        }
      ],
      "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-478",
              "description": "CWE-478: Missing Default Case in Multiple Condition Expression",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-03-20T08:00:31.755Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/free5gc/free5gc/security/advisories/GHSA-7g27-v5wj-jr75",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/free5gc/free5gc/security/advisories/GHSA-7g27-v5wj-jr75"
        },
        {
          "name": "https://github.com/free5gc/free5gc/issues/781",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/free5gc/free5gc/issues/781"
        },
        {
          "name": "https://github.com/free5gc/udm/pull/78",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/free5gc/udm/pull/78"
        },
        {
          "name": "https://github.com/free5gc/udm/commit/65d7070f4bfd016864cbbaefbd506bbc85d2fa92",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/free5gc/udm/commit/65d7070f4bfd016864cbbaefbd506bbc85d2fa92"
        }
      ],
      "source": {
        "advisory": "GHSA-7g27-v5wj-jr75",
        "discovery": "UNKNOWN"
      },
      "title": "free5GC UDM DataChangeNotification Procedure Panic Due to Nil Pointer Dereference"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-33064",
    "datePublished": "2026-03-20T08:00:31.755Z",
    "dateReserved": "2026-03-17T19:27:06.343Z",
    "dateUpdated": "2026-03-20T15:42:53.709Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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

GHSA-7G27-V5WJ-JR75

CVE-2026-33064 (GCVE-0-2026-33064)

Tags

Sightings

Nomenclature