Vulnerability-Lookup

CNVD-2021-39030

Vulnerability from cnvd - Published: 2021-06-03

Title

Nextcloud存在未明漏洞（CNVD-2021-39030）

Description

Nextcloud是德国Nextcloud公司的一套开源的自托管文件同步和共享的通信应用平台。 Nextcloud Server存在安全漏洞，攻击者可利用该漏洞通过访问合法服务器用户添加为联邦共享的公共链接来访问服务器用户的基本信息。

Severity

高

Patch Name

Nextcloud存在未明漏洞（CNVD-2021-39030）的补丁

Patch Description

Nextcloud是德国Nextcloud公司的一套开源的自托管文件同步和共享的通信应用平台。 Nextcloud Server存在安全漏洞，攻击者可利用该漏洞通过访问合法服务器用户添加为联邦共享的公共链接来访问服务器用户的基本信息。目前，供应商发布了安全公告及相关补丁信息，修复了此漏洞。

Formal description

厂商已发布了漏洞修复程序，请及时关注更新： https://github.com/nextcloud/security-advisories/security/advisories/GHSA-j875-vr2q-h6x6

Reference

https://hackerone.com/reports/1167853

Impacted products

Name
['Nextcloud Nextcloud Server 19.0.11', 'Nextcloud Nextcloud Server 20.0.10', 'Nextcloud Nextcloud Server <21.0.2']

Show details on source website

JSON

To clipboard

{
  "cves": {
    "cve": {
      "cveNumber": "CVE-2021-32656"
    }
  },
  "description": "Nextcloud\u662f\u5fb7\u56fdNextcloud\u516c\u53f8\u7684\u4e00\u5957\u5f00\u6e90\u7684\u81ea\u6258\u7ba1\u6587\u4ef6\u540c\u6b65\u548c\u5171\u4eab\u7684\u901a\u4fe1\u5e94\u7528\u5e73\u53f0\u3002\n\nNextcloud Server\u5b58\u5728\u5b89\u5168\u6f0f\u6d1e\uff0c\u653b\u51fb\u8005\u53ef\u5229\u7528\u8be5\u6f0f\u6d1e\u901a\u8fc7\u8bbf\u95ee\u5408\u6cd5\u670d\u52a1\u5668\u7528\u6237\u6dfb\u52a0\u4e3a\u8054\u90a6\u5171\u4eab\u7684\u516c\u5171\u94fe\u63a5\u6765\u8bbf\u95ee\u670d\u52a1\u5668\u7528\u6237\u7684\u57fa\u672c\u4fe1\u606f\u3002",
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  "isEvent": "\u901a\u7528\u8f6f\u786c\u4ef6\u6f0f\u6d1e",
  "number": "CNVD-2021-39030",
  "openTime": "2021-06-03",
  "patchDescription": "Nextcloud\u662f\u5fb7\u56fdNextcloud\u516c\u53f8\u7684\u4e00\u5957\u5f00\u6e90\u7684\u81ea\u6258\u7ba1\u6587\u4ef6\u540c\u6b65\u548c\u5171\u4eab\u7684\u901a\u4fe1\u5e94\u7528\u5e73\u53f0\u3002\r\n\r\nNextcloud Server\u5b58\u5728\u5b89\u5168\u6f0f\u6d1e\uff0c\u653b\u51fb\u8005\u53ef\u5229\u7528\u8be5\u6f0f\u6d1e\u901a\u8fc7\u8bbf\u95ee\u5408\u6cd5\u670d\u52a1\u5668\u7528\u6237\u6dfb\u52a0\u4e3a\u8054\u90a6\u5171\u4eab\u7684\u516c\u5171\u94fe\u63a5\u6765\u8bbf\u95ee\u670d\u52a1\u5668\u7528\u6237\u7684\u57fa\u672c\u4fe1\u606f\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": "Nextcloud\u5b58\u5728\u672a\u660e\u6f0f\u6d1e\uff08CNVD-2021-39030\uff09\u7684\u8865\u4e01",
  "products": {
    "product": [
      "Nextcloud Nextcloud Server 19.0.11",
      "Nextcloud Nextcloud Server 20.0.10",
      "Nextcloud Nextcloud Server \u003c21.0.2"
    ]
  },
  "referenceLink": "https://hackerone.com/reports/1167853",
  "serverity": "\u9ad8",
  "submitTime": "2021-06-03",
  "title": "Nextcloud\u5b58\u5728\u672a\u660e\u6f0f\u6d1e\uff08CNVD-2021-39030\uff09"
}

CVE-2021-32656 (GCVE-0-2021-32656)

Vulnerability from cvelistv5 – Published: 2021-06-01 21:45 – Updated: 2024-08-03 23:25

Title

Trusted servers exchange can be triggered by attacker

Summary

Nextcloud Server is a Nextcloud package that handles data storage. A vulnerability in federated share exists in versions prior to 19.0.11, 20.0.10, and 21.0.2. An attacker can gain access to basic information about users of a server by accessing a public link that a legitimate server user added as a federated share. This happens because Nextcloud supports sharing registered users with other Nextcloud servers, which can be done automatically when selecting the "Add server automatically once a federated share was created successfully" setting. The vulnerability is patched in versions 19.0.11, 20.0.10, and 21.0.2 As a workaround, disable "Add server automatically once a federated share was created successfully" in the Nextcloud settings.

Severity

8.6 (High)


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

CWE

CWE-284 - Improper Access Control

Assigner

GitHub_M mitre root

References

3 references

URL	Tags
https://github.com/nextcloud/security-advisories/…	x_refsource_CONFIRM
https://hackerone.com/reports/1167853	x_refsource_MISC
https://security.gentoo.org/glsa/202208-17	vendor-advisoryx_refsource_GENTOO

Impacted products

1 product

Vendor	Product	Version
nextcloud	security-advisories	Affected: < 19.0.11 Affected: >= 20.0.0, < 20.0.10 Affected: >= 21.0.0, < 21.0.2

Show details on NVD website

JSON

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              "x_refsource_GENTOO",
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            "url": "https://security.gentoo.org/glsa/202208-17"
          }
        ],
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      }
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          "vendor": "nextcloud",
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        {
          "lang": "en",
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        },
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        "discovery": "UNKNOWN"
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Sightings

Author	Source	Type	Date	Other

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.

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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.