Vulnerability-Lookup

CNVD-2016-09674

Vulnerability from cnvd - Published: 2016-10-21

Title

OpenSSH远程拒绝服务漏洞（CNVD-2016-09674）

Description

OpenSSH（OpenBSD Secure Shell）是OpenBSD计划组所维护的一套用于安全访问远程计算机的连接工具。 OpenSSH在秘钥交换过程中kex_input_kexinit()函数存在内存耗尽问题，未经认证的客户端可通过重复KEXINIT过程，使服务器上每个连接的内存分配增加至384MB。攻击者利用该漏洞可发起多个连接，使服务器的内存耗尽，造成拒绝服务攻击。

Severity

高

Patch Name

OpenSSH远程拒绝服务漏洞（CNVD-2016-09674）的补丁

Patch Description

OpenSSH（OpenBSD Secure Shell）是OpenBSD计划组所维护的一套用于安全访问远程计算机的连接工具。 OpenSSH在秘钥交换过程中kex_input_kexinit()函数存在一个内存耗尽问题，一个未经认证的客户端，可以通过重复KEXINIT过程，使服务器上每个连接的内存分配增加至384MB，攻击者利用该漏洞，可发起多个连接，使服务器的内存耗尽，造成拒绝服务攻击。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

目厂商提供了源代码的修复，建议用户对源代码进行升级和编译。代码修复链接如下： http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/kex.c#rev1.127

Reference

http://www.securitytracker.com/id/1037057

Impacted products

Name
OpenSSH OpenSSH

Show details on source website

JSON

To clipboard

{
  "cves": {
    "cve": {
      "cveNumber": "CVE-2016-8858"
    }
  },
  "description": "OpenSSH\uff08OpenBSD Secure Shell\uff09\u662fOpenBSD\u8ba1\u5212\u7ec4\u6240\u7ef4\u62a4\u7684\u4e00\u5957\u7528\u4e8e\u5b89\u5168\u8bbf\u95ee\u8fdc\u7a0b\u8ba1\u7b97\u673a\u7684\u8fde\u63a5\u5de5\u5177\u3002\r\n\r\nOpenSSH\u5728\u79d8\u94a5\u4ea4\u6362\u8fc7\u7a0b\u4e2dkex_input_kexinit()\u51fd\u6570\u5b58\u5728\u5185\u5b58\u8017\u5c3d\u95ee\u9898\uff0c\u672a\u7ecf\u8ba4\u8bc1\u7684\u5ba2\u6237\u7aef\u53ef\u901a\u8fc7\u91cd\u590dKEXINIT\u8fc7\u7a0b\uff0c\u4f7f\u670d\u52a1\u5668\u4e0a\u6bcf\u4e2a\u8fde\u63a5\u7684\u5185\u5b58\u5206\u914d\u589e\u52a0\u81f3384MB\u3002\u653b\u51fb\u8005\u5229\u7528\u8be5\u6f0f\u6d1e\u53ef\u53d1\u8d77\u591a\u4e2a\u8fde\u63a5\uff0c\u4f7f\u670d\u52a1\u5668\u7684\u5185\u5b58\u8017\u5c3d\uff0c\u9020\u6210\u62d2\u7edd\u670d\u52a1\u653b\u51fb\u3002",
  "discovererName": "Shi Lei",
  "formalWay": "\u76ee\u5382\u5546\u63d0\u4f9b\u4e86\u6e90\u4ee3\u7801\u7684\u4fee\u590d\uff0c\u5efa\u8bae\u7528\u6237\u5bf9\u6e90\u4ee3\u7801\u8fdb\u884c\u5347\u7ea7\u548c\u7f16\u8bd1\u3002\u4ee3\u7801\u4fee\u590d\u94fe\u63a5\u5982\u4e0b\uff1a\r\nhttp://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/kex.c#rev1.127",
  "isEvent": "\u901a\u7528\u8f6f\u786c\u4ef6\u6f0f\u6d1e",
  "number": "CNVD-2016-09674",
  "openTime": "2016-10-21",
  "patchDescription": "OpenSSH\uff08OpenBSD Secure Shell\uff09\u662fOpenBSD\u8ba1\u5212\u7ec4\u6240\u7ef4\u62a4\u7684\u4e00\u5957\u7528\u4e8e\u5b89\u5168\u8bbf\u95ee\u8fdc\u7a0b\u8ba1\u7b97\u673a\u7684\u8fde\u63a5\u5de5\u5177\u3002\r\n\r\nOpenSSH\u5728\u79d8\u94a5\u4ea4\u6362\u8fc7\u7a0b\u4e2dkex_input_kexinit()\u51fd\u6570\u5b58\u5728\u4e00\u4e2a\u5185\u5b58\u8017\u5c3d\u95ee\u9898\uff0c\u4e00\u4e2a\u672a\u7ecf\u8ba4\u8bc1\u7684\u5ba2\u6237\u7aef\uff0c\u53ef\u4ee5\u901a\u8fc7\u91cd\u590dKEXINIT\u8fc7\u7a0b\uff0c\u4f7f\u670d\u52a1\u5668\u4e0a\u6bcf\u4e2a\u8fde\u63a5\u7684\u5185\u5b58\u5206\u914d\u589e\u52a0\u81f3384MB\uff0c\u653b\u51fb\u8005\u5229\u7528\u8be5\u6f0f\u6d1e\uff0c\u53ef\u53d1\u8d77\u591a\u4e2a\u8fde\u63a5\uff0c\u4f7f\u670d\u52a1\u5668\u7684\u5185\u5b58\u8017\u5c3d\uff0c\u9020\u6210\u62d2\u7edd\u670d\u52a1\u653b\u51fb\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": "OpenSSH\u8fdc\u7a0b\u62d2\u7edd\u670d\u52a1\u6f0f\u6d1e\uff08CNVD-2016-09674\uff09\u7684\u8865\u4e01",
  "products": {
    "product": "OpenSSH OpenSSH"
  },
  "referenceLink": "http://www.securitytracker.com/id/1037057",
  "serverity": "\u9ad8",
  "submitTime": "2016-10-21",
  "title": "OpenSSH\u8fdc\u7a0b\u62d2\u7edd\u670d\u52a1\u6f0f\u6d1e\uff08CNVD-2016-09674\uff09"
}

CVE-2016-8858 (GCVE-0-2016-8858)

Vulnerability from cvelistv5 – Published: 2016-12-09 00:00 – Updated: 2026-05-29 20:45 Disputed

Summary

The kex_input_kexinit function in kex.c in OpenSSH 6.x and 7.x through 7.3 allows remote attackers to cause a denial of service (memory consumption) by sending many duplicate KEXINIT requests. NOTE: a third party reports that "OpenSSH upstream does not consider this as a security issue."

Severity

7.5 (High)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2024-04-15 16:36 UTC

CWE

n/a
CWE-400 - Uncontrolled Resource Consumption

Assigner

mitre mitre root

References

13 references

URL	Tags
http://www.securityfocus.com/bid/93776	vdb-entry
http://www.openwall.com/lists/oss-security/2016/10/20/1	mailing-list
https://security.netapp.com/advisory/ntap-2018020…
http://www.openwall.com/lists/oss-security/2016/10/19/3	mailing-list
http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.…
https://github.com/openssh/openssh-portable/commi…
https://ftp.openbsd.org/pub/OpenBSD/patches/6.0/c…
https://security.FreeBSD.org/advisories/FreeBSD-S…	vendor-advisory
http://www.securitytracker.com/id/1037057	vdb-entry
https://security.gentoo.org/glsa/201612-18	vendor-advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1384860
http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.…
https://cert-portal.siemens.com/productcert/pdf/s…

Date Public

2016-10-10 00:00

Show details on NVD website

JSON

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{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-06T02:35:01.046Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
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        "references": [
          {
            "name": "93776",
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              "vdb-entry",
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            "url": "http://www.securityfocus.com/bid/93776"
          },
          {
            "name": "[oss-security] 20161020 Re: Re: CVE Request: OpenSSH: Memory exhaustion issue found in OpenSSH",
            "tags": [
              "mailing-list",
              "x_transferred"
            ],
            "url": "http://www.openwall.com/lists/oss-security/2016/10/20/1"
          },
          {
            "tags": [
              "x_transferred"
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            "url": "https://security.netapp.com/advisory/ntap-20180201-0001/"
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            "name": "[oss-security] 20161019 CVE Request: OpenSSH: Memory exhaustion issue found in OpenSSH",
            "tags": [
              "mailing-list",
              "x_transferred"
            ],
            "url": "http://www.openwall.com/lists/oss-security/2016/10/19/3"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/kex.c.diff?r1=1.126\u0026r2=1.127\u0026f=h"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://github.com/openssh/openssh-portable/commit/ec165c392ca54317dbe3064a8c200de6531e89ad"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://ftp.openbsd.org/pub/OpenBSD/patches/6.0/common/013_ssh_kexinit.patch.sig"
          },
          {
            "name": "FreeBSD-SA-16:33",
            "tags": [
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          },
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            "name": "GLSA-201612-18",
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            "url": "https://bugzilla.redhat.com/show_bug.cgi?id=1384860"
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            ],
            "url": "http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/kex.c?rev=1.127\u0026content-type=text/x-cvsweb-markup"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://cert-portal.siemens.com/productcert/pdf/ssa-412672.pdf"
          }
        ],
        "title": "CVE Program Container"
      },
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "NETWORK",
              "availabilityImpact": "HIGH",
              "baseScore": 7.5,
              "baseSeverity": "HIGH",
              "confidentialityImpact": "NONE",
              "integrityImpact": "NONE",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2016-8858",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2024-04-15T16:36:39.938823Z",
                "version": "2.0.3"
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              "type": "ssvc"
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        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-400",
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            ]
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        ],
        "providerMetadata": {
          "dateUpdated": "2026-05-29T20:45:20.720Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
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          "product": "n/a",
          "vendor": "n/a",
          "versions": [
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      ],
      "problemTypes": [
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      "providerMetadata": {
        "dateUpdated": "2022-12-13T00:00:00.000Z",
        "orgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
        "shortName": "mitre"
      },
      "references": [
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          "name": "93776",
          "tags": [
            "vdb-entry"
          ],
          "url": "http://www.securityfocus.com/bid/93776"
        },
        {
          "name": "[oss-security] 20161020 Re: Re: CVE Request: OpenSSH: Memory exhaustion issue found in OpenSSH",
          "tags": [
            "mailing-list"
          ],
          "url": "http://www.openwall.com/lists/oss-security/2016/10/20/1"
        },
        {
          "url": "https://security.netapp.com/advisory/ntap-20180201-0001/"
        },
        {
          "name": "[oss-security] 20161019 CVE Request: OpenSSH: Memory exhaustion issue found in OpenSSH",
          "tags": [
            "mailing-list"
          ],
          "url": "http://www.openwall.com/lists/oss-security/2016/10/19/3"
        },
        {
          "url": "http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/kex.c.diff?r1=1.126\u0026r2=1.127\u0026f=h"
        },
        {
          "url": "https://github.com/openssh/openssh-portable/commit/ec165c392ca54317dbe3064a8c200de6531e89ad"
        },
        {
          "url": "https://ftp.openbsd.org/pub/OpenBSD/patches/6.0/common/013_ssh_kexinit.patch.sig"
        },
        {
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          "tags": [
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        },
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          "tags": [
            "vdb-entry"
          ],
          "url": "http://www.securitytracker.com/id/1037057"
        },
        {
          "name": "GLSA-201612-18",
          "tags": [
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        },
        {
          "url": "https://bugzilla.redhat.com/show_bug.cgi?id=1384860"
        },
        {
          "url": "http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/kex.c?rev=1.127\u0026content-type=text/x-cvsweb-markup"
        },
        {
          "url": "https://cert-portal.siemens.com/productcert/pdf/ssa-412672.pdf"
        }
      ],
      "tags": [
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      ]
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  },
  "cveMetadata": {
    "assignerOrgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
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    "datePublished": "2016-12-09T00:00:00.000Z",
    "dateReserved": "2016-10-19T00:00:00.000Z",
    "dateUpdated": "2026-05-29T20:45:20.720Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.