Vulnerability-Lookup

CNVD-2026-37852

Vulnerability from cnvd - Published: 2026-09-15

Title

free5GC空字节注入漏洞

Description

free5GC是一个‌开源的5G核心网项目‌，由Linux基金会托管，主要用来实现3GPP标准里定义的5G核心网络功能。 free5GC存在空字节注入漏洞，该漏洞源于UDM的Nudm_SubscriberDataManagement API在处理supi路径参数时，未能正确过滤URL编码的空字节（%00）。攻击者可利用该漏洞通过注入空字节导致URL解析失败并触发500内部服务器错误，导致拒绝服务。

Severity

高

Patch Name

free5GC空字节注入漏洞的补丁

Patch Description

Formal description

目前厂商已发布升级程序修复该安全问题，详情见厂商官网: https://github.com/free5gc/udm/releases

Reference

https://github.com/free5gc/free5gc/security/advisories/GHSA-p9hg-pq3q-v9gv https://github.com/free5gc/udm/commit/88de9fa74a1b3f3522e53b4cfa2d184712ffa4ee

Impacted products

Name
free5GC free5GC <1.4.2

Show details on source website

JSON

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{
  "cves": {
    "cve": {
      "cveNumber": "CVE-2026-33191",
      "cveUrl": "https://nvd.nist.gov/vuln/detail/CVE-2026-33191"
    }
  },
  "description": "free5GC\u662f\u4e00\u4e2a\u200c\u5f00\u6e90\u76845G\u6838\u5fc3\u7f51\u9879\u76ee\u200c\uff0c\u7531Linux\u57fa\u91d1\u4f1a\u6258\u7ba1\uff0c\u4e3b\u8981\u7528\u6765\u5b9e\u73b03GPP\u6807\u51c6\u91cc\u5b9a\u4e49\u76845G\u6838\u5fc3\u7f51\u7edc\u529f\u80fd\u3002\n\nfree5GC\u5b58\u5728\u7a7a\u5b57\u8282\u6ce8\u5165\u6f0f\u6d1e\uff0c\u8be5\u6f0f\u6d1e\u6e90\u4e8eUDM\u7684Nudm_SubscriberDataManagement API\u5728\u5904\u7406supi\u8def\u5f84\u53c2\u6570\u65f6\uff0c\u672a\u80fd\u6b63\u786e\u8fc7\u6ee4URL\u7f16\u7801\u7684\u7a7a\u5b57\u8282\uff08%00\uff09\u3002\u653b\u51fb\u8005\u53ef\u5229\u7528\u8be5\u6f0f\u6d1e\u901a\u8fc7\u6ce8\u5165\u7a7a\u5b57\u8282\u5bfc\u81f4URL\u89e3\u6790\u5931\u8d25\u5e76\u89e6\u53d1500\u5185\u90e8\u670d\u52a1\u5668\u9519\u8bef\uff0c\u5bfc\u81f4\u62d2\u7edd\u670d\u52a1\u3002",
  "formalWay": "\u76ee\u524d\u5382\u5546\u5df2\u53d1\u5e03\u5347\u7ea7\u7a0b\u5e8f\u4fee\u590d\u8be5\u5b89\u5168\u95ee\u9898\uff0c\u8be6\u60c5\u89c1\u5382\u5546\u5b98\u7f51:\r\nhttps://github.com/free5gc/udm/releases",
  "isEvent": "\u901a\u7528\u8f6f\u786c\u4ef6\u6f0f\u6d1e",
  "number": "CNVD-2026-37852",
  "openTime": "2026-09-15",
  "patchDescription": "free5GC\u662f\u4e00\u4e2a\u200c\u5f00\u6e90\u76845G\u6838\u5fc3\u7f51\u9879\u76ee\u200c\uff0c\u7531Linux\u57fa\u91d1\u4f1a\u6258\u7ba1\uff0c\u4e3b\u8981\u7528\u6765\u5b9e\u73b03GPP\u6807\u51c6\u91cc\u5b9a\u4e49\u76845G\u6838\u5fc3\u7f51\u7edc\u529f\u80fd\u3002\r\n\r\nfree5GC\u5b58\u5728\u7a7a\u5b57\u8282\u6ce8\u5165\u6f0f\u6d1e\uff0c\u8be5\u6f0f\u6d1e\u6e90\u4e8eUDM\u7684Nudm_SubscriberDataManagement API\u5728\u5904\u7406supi\u8def\u5f84\u53c2\u6570\u65f6\uff0c\u672a\u80fd\u6b63\u786e\u8fc7\u6ee4URL\u7f16\u7801\u7684\u7a7a\u5b57\u8282\uff08%00\uff09\u3002\u653b\u51fb\u8005\u53ef\u5229\u7528\u8be5\u6f0f\u6d1e\u901a\u8fc7\u6ce8\u5165\u7a7a\u5b57\u8282\u5bfc\u81f4URL\u89e3\u6790\u5931\u8d25\u5e76\u89e6\u53d1500\u5185\u90e8\u670d\u52a1\u5668\u9519\u8bef\uff0c\u5bfc\u81f4\u62d2\u7edd\u670d\u52a1\u3002\u76ee\u524d\uff0c\u4f9b\u5e94\u5546\u53d1\u5e03\u4e86\u5b89\u5168\u516c\u544a\u53ca\u76f8\u5173\u8865\u4e01\u4fe1\u606f\uff0c\u4fee\u590d\u4e86\u6b64\u6f0f\u6d1e\u3002",
  "patchName": "free5GC\u7a7a\u5b57\u8282\u6ce8\u5165\u6f0f\u6d1e\u7684\u8865\u4e01",
  "products": {
    "product": "free5GC free5GC \u003c1.4.2"
  },
  "referenceLink": "https://github.com/free5gc/free5gc/security/advisories/GHSA-p9hg-pq3q-v9gv\r\nhttps://github.com/free5gc/udm/commit/88de9fa74a1b3f3522e53b4cfa2d184712ffa4ee",
  "serverity": "\u9ad8",
  "submitTime": "2026-03-24",
  "title": "free5GC\u7a7a\u5b57\u8282\u6ce8\u5165\u6f0f\u6d1e"
}

CVE-2026-33191 (GCVE-0-2026-33191)

Vulnerability from cvelistv5 – Published: 2026-03-20 07:54 – Updated: 2026-03-20 19:36

Title

free5GC UDM vulnerable to null byte injection in URL path parameters causing 500 Internal Server Error

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 null byte injection in URL path parameters. A remote attacker can inject null bytes (URL-encoded as %00) into the supi path parameter of the UDM's Nudm_SubscriberDataManagement API. This causes URL parsing failure in Go's net/url package with the error "invalid control character in URL", resulting in a 500 Internal Server Error. This null byte injection vulnerability can be exploited for denial of service attacks. When the supi parameter contains null characters, the UDM attempts to construct a URL for UDR that includes these control characters. Go's URL parser rejects them, causing the request to fail with 500 instead of properly validating input and returning 400 Bad Request. 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

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-03-20 19:35 UTC

CWE

CWE-158 - Improper Neutralization of Null Byte or NUL Character
CWE-248 - Uncaught Exception

Assigner

GitHub_M mitre root

References

2 references

URL	Tags
https://github.com/free5gc/free5gc/security/advis…	x_refsource_CONFIRM
https://github.com/free5gc/udm/commit/88de9fa74a1…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
free5gc	free5gc	Affected: < 1.4.2

Show details on NVD website

JSON

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-33191",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-03-20T19:35:49.317638Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
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        ],
        "providerMetadata": {
          "dateUpdated": "2026-03-20T19:36:09.548Z",
          "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\nare vulnerable to null byte injection in URL path parameters. A remote attacker can inject null bytes (URL-encoded as %00) into the supi path parameter of the UDM\u0027s Nudm_SubscriberDataManagement API. This causes URL parsing failure in Go\u0027s net/url package with the error \"invalid control character in URL\", resulting in a 500 Internal Server Error. This null byte injection vulnerability can be exploited for denial of service attacks. When the supi parameter contains null characters, the UDM attempts to construct a URL for UDR that includes these control characters. Go\u0027s URL parser rejects them, causing the request to fail with 500 instead of properly validating input and returning 400 Bad Request. 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"
          }
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      ],
      "problemTypes": [
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          "descriptions": [
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              "description": "CWE-158: Improper Neutralization of Null Byte or NUL Character",
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        },
        {
          "descriptions": [
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              "description": "CWE-248: Uncaught Exception",
              "lang": "en",
              "type": "CWE"
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      "providerMetadata": {
        "dateUpdated": "2026-03-20T07:54:26.539Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
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      "references": [
        {
          "name": "https://github.com/free5gc/free5gc/security/advisories/GHSA-p9hg-pq3q-v9gv",
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        },
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          "url": "https://github.com/free5gc/udm/commit/88de9fa74a1b3f3522e53b4cfa2d184712ffa4ee"
        }
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      "source": {
        "advisory": "GHSA-p9hg-pq3q-v9gv",
        "discovery": "UNKNOWN"
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    "dateReserved": "2026-03-17T22:16:36.721Z",
    "dateUpdated": "2026-03-20T19:36:09.548Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

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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.
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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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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CNVD-2026-37852

CVE-2026-33191 (GCVE-0-2026-33191)

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