Vulnerability-Lookup

CNVD-2021-83669

Vulnerability from cnvd - Published: 2021-10-25

Title

Snudown加密问题漏洞

Description

Snudown是开源的一个软件包。是 GitHub 使用的Sundown Markdown 解析器的 reddit 特定分支，添加了 Python 集成。 Snudown存在加密问题漏洞，攻击者可以利用该漏洞进行DoS攻击。

Severity

中

Patch Name

Snudown加密问题漏洞的补丁

Patch Description

Snudown是开源的一个软件包。是 GitHub 使用的Sundown Markdown 解析器的 reddit 特定分支，添加了 Python 集成。 Snudown存在加密问题漏洞，攻击者可以利用该漏洞进行DoS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

目前厂商已发布升级补丁以修复漏洞，补丁获取链接： https://github.com/reddit/snudown/commit/1ac2c130b210539ee1e5d67a7bac93f9d8007c0e

Reference

https://nvd.nist.gov/vuln/detail/CVE-2021-41168

Impacted products

Name
Snudown Snudown <1.7.0

Show details on source website

JSON

To clipboard

{
  "cves": {
    "cve": {
      "cveNumber": "CVE-2021-41168"
    }
  },
  "description": "Snudown\u662f\u5f00\u6e90\u7684\u4e00\u4e2a\u8f6f\u4ef6\u5305\u3002\u662f GitHub \u4f7f\u7528\u7684Sundown Markdown \u89e3\u6790\u5668\u7684 reddit \u7279\u5b9a\u5206\u652f\uff0c\u6dfb\u52a0\u4e86 Python \u96c6\u6210\u3002\n\nSnudown\u5b58\u5728\u52a0\u5bc6\u95ee\u9898\u6f0f\u6d1e\uff0c\u653b\u51fb\u8005\u53ef\u4ee5\u5229\u7528\u8be5\u6f0f\u6d1e\u8fdb\u884cDoS\u653b\u51fb\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/reddit/snudown/commit/1ac2c130b210539ee1e5d67a7bac93f9d8007c0e",
  "isEvent": "\u901a\u7528\u8f6f\u786c\u4ef6\u6f0f\u6d1e",
  "number": "CNVD-2021-83669",
  "openTime": "2021-10-25",
  "patchDescription": "Snudown\u662f\u5f00\u6e90\u7684\u4e00\u4e2a\u8f6f\u4ef6\u5305\u3002\u662f GitHub \u4f7f\u7528\u7684Sundown Markdown \u89e3\u6790\u5668\u7684 reddit \u7279\u5b9a\u5206\u652f\uff0c\u6dfb\u52a0\u4e86 Python \u96c6\u6210\u3002\r\n\r\nSnudown\u5b58\u5728\u52a0\u5bc6\u95ee\u9898\u6f0f\u6d1e\uff0c\u653b\u51fb\u8005\u53ef\u4ee5\u5229\u7528\u8be5\u6f0f\u6d1e\u8fdb\u884cDoS\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": "Snudown\u52a0\u5bc6\u95ee\u9898\u6f0f\u6d1e\u7684\u8865\u4e01",
  "products": {
    "product": "Snudown Snudown \u003c1.7.0"
  },
  "referenceLink": "https://nvd.nist.gov/vuln/detail/CVE-2021-41168",
  "serverity": "\u4e2d",
  "submitTime": "2021-10-25",
  "title": "Snudown\u52a0\u5bc6\u95ee\u9898\u6f0f\u6d1e"
}

CVE-2021-41168 (GCVE-0-2021-41168)

Vulnerability from cvelistv5 – Published: 2021-10-21 20:10 – Updated: 2024-08-04 02:59

Title

Hash-Collision Denial-of-Service Vulnerability in snudown

Summary

Snudown is a reddit-specific fork of the Sundown Markdown parser used by GitHub, with Python integration added. In affected versions snudown was found to be vulnerable to denial of service attacks to its reference table implementation. References written in markdown ` [reference_name]: https://www.example.com` are inserted into a hash table which was found to have a weak hash function, meaning that an attacker can reliably generate a large number of collisions for it. This makes the hash table vulnerable to a hash-collision DoS attack, a type of algorithmic complexity attack. Further the hash table allowed for duplicate entries resulting in long retrieval times. Proofs of concept and further discussion of the hash collision issue are discussed on the snudown GHSA(https://github.com/reddit/snudown/security/advisories/GHSA-6gvv-9q92-w5f6). Users are advised to update to version 1.7.0.

Severity

6.5 (Medium)


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

CWE

CWE-400 - Uncontrolled Resource Consumption
CWE-20 - Improper Input Validation
CWE-327 - Use of a Broken or Risky Cryptographic Algorithm

Assigner

GitHub_M mitre root

References

2 references

URL	Tags
https://github.com/reddit/snudown/security/adviso…	x_refsource_CONFIRM
https://github.com/reddit/snudown/commit/1ac2c130…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
reddit	snudown	Affected: < 1.7.0

Show details on NVD website

JSON

To clipboard

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          },
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            "url": "https://github.com/reddit/snudown/commit/1ac2c130b210539ee1e5d67a7bac93f9d8007c0e"
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        }
      ],
      "metrics": [
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        },
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        }
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        "discovery": "UNKNOWN"
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      "title": "Hash-Collision Denial-of-Service Vulnerability in snudown",
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        },
        "affects": {
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            "vendor_data": [
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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.