Vulnerability-Lookup

CNVD-2020-36781

Vulnerability from cnvd - Published: 2020-07-07

Title

LibVNCServer缓冲区溢出漏洞（CNVD-2020-36781）

Description

LibVNCServer是一款支持在程序中实现VNC（虚拟网络计算）服务器或客户端功能的跨平台C语言库。 LibVNCServer 0.9.13之前版本中的libvncserver/ws_decode.c文件的‘hybiReadAndDecode’函数存在安全漏洞。攻击者可利用该漏洞导致拒绝服务（崩溃）。

Severity

中

Patch Name

LibVNCServer缓冲区溢出漏洞（CNVD-2020-36781）的补丁

Patch Description

Formal description

目前厂商已发布升级补丁以修复漏洞，补丁获取链接： https://github.com/LibVNC/libvncserver/commit/0cf1400c61850065de590d403f6d49e32882fd76

Reference

https://nvd.nist.gov/vuln/detail/CVE-2019-20840

Impacted products

Name
LibVNCServer LibVNCServer <0.9.13

Show details on source website

JSON

To clipboard

{
  "cves": {
    "cve": {
      "cveNumber": "CVE-2019-20840"
    }
  },
  "description": "LibVNCServer\u662f\u4e00\u6b3e\u652f\u6301\u5728\u7a0b\u5e8f\u4e2d\u5b9e\u73b0VNC\uff08\u865a\u62df\u7f51\u7edc\u8ba1\u7b97\uff09\u670d\u52a1\u5668\u6216\u5ba2\u6237\u7aef\u529f\u80fd\u7684\u8de8\u5e73\u53f0C\u8bed\u8a00\u5e93\u3002\n\nLibVNCServer 0.9.13\u4e4b\u524d\u7248\u672c\u4e2d\u7684libvncserver/ws_decode.c\u6587\u4ef6\u7684\u2018hybiReadAndDecode\u2019\u51fd\u6570\u5b58\u5728\u5b89\u5168\u6f0f\u6d1e\u3002\u653b\u51fb\u8005\u53ef\u5229\u7528\u8be5\u6f0f\u6d1e\u5bfc\u81f4\u62d2\u7edd\u670d\u52a1\uff08\u5d29\u6e83\uff09\u3002",
  "formalWay": "\u76ee\u524d\u5382\u5546\u5df2\u53d1\u5e03\u5347\u7ea7\u8865\u4e01\u4ee5\u4fee\u590d\u6f0f\u6d1e\uff0c\u8865\u4e01\u83b7\u53d6\u94fe\u63a5\uff1a\r\nhttps://github.com/LibVNC/libvncserver/commit/0cf1400c61850065de590d403f6d49e32882fd76",
  "isEvent": "\u901a\u7528\u8f6f\u786c\u4ef6\u6f0f\u6d1e",
  "number": "CNVD-2020-36781",
  "openTime": "2020-07-07",
  "patchDescription": "LibVNCServer\u662f\u4e00\u6b3e\u652f\u6301\u5728\u7a0b\u5e8f\u4e2d\u5b9e\u73b0VNC\uff08\u865a\u62df\u7f51\u7edc\u8ba1\u7b97\uff09\u670d\u52a1\u5668\u6216\u5ba2\u6237\u7aef\u529f\u80fd\u7684\u8de8\u5e73\u53f0C\u8bed\u8a00\u5e93\u3002\r\n\r\nLibVNCServer 0.9.13\u4e4b\u524d\u7248\u672c\u4e2d\u7684libvncserver/ws_decode.c\u6587\u4ef6\u7684\u2018hybiReadAndDecode\u2019\u51fd\u6570\u5b58\u5728\u5b89\u5168\u6f0f\u6d1e\u3002\u653b\u51fb\u8005\u53ef\u5229\u7528\u8be5\u6f0f\u6d1e\u5bfc\u81f4\u62d2\u7edd\u670d\u52a1\uff08\u5d29\u6e83\uff09\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": "LibVNCServer\u7f13\u51b2\u533a\u6ea2\u51fa\u6f0f\u6d1e\uff08CNVD-2020-36781\uff09\u7684\u8865\u4e01",
  "products": {
    "product": "LibVNCServer LibVNCServer \u003c0.9.13"
  },
  "referenceLink": "https://nvd.nist.gov/vuln/detail/CVE-2019-20840",
  "serverity": "\u4e2d",
  "submitTime": "2020-06-18",
  "title": "LibVNCServer\u7f13\u51b2\u533a\u6ea2\u51fa\u6f0f\u6d1e\uff08CNVD-2020-36781\uff09"
}

CVE-2019-20840 (GCVE-0-2019-20840)

Vulnerability from cvelistv5 – Published: 2020-06-17 15:11 – Updated: 2024-08-05 02:53

Summary

An issue was discovered in LibVNCServer before 0.9.13. libvncserver/ws_decode.c can lead to a crash because of unaligned accesses in hybiReadAndDecode.

Severity

No CVSS data available.

CWE

Assigner

mitre CNA under the mitre root

CNA scorecard E 28/100 over 2350 records in the last 180 days details

References

8 references

URL	Tags
https://github.com/LibVNC/libvncserver/compare/Li…	x_refsource_MISC
https://github.com/LibVNC/libvncserver/commit/0cf…	x_refsource_MISC
https://lists.fedoraproject.org/archives/list/pac…	vendor-advisoryx_refsource_FEDORA
http://lists.opensuse.org/opensuse-security-annou…	vendor-advisoryx_refsource_SUSE
http://lists.opensuse.org/opensuse-security-annou…	vendor-advisoryx_refsource_SUSE
http://lists.opensuse.org/opensuse-security-annou…	vendor-advisoryx_refsource_SUSE
https://usn.ubuntu.com/4434-1/	vendor-advisoryx_refsource_UBUNTU
https://cert-portal.siemens.com/productcert/pdf/s…	x_refsource_CONFIRM

Show details on NVD website

JSON

To clipboard

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          },
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            "url": "https://github.com/LibVNC/libvncserver/commit/0cf1400c61850065de590d403f6d49e32882fd76"
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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.

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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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