Vulnerability-Lookup

GHSA-8J9V-H2VP-2HHV

Vulnerability from github – Published: 2021-01-04 18:22 – Updated: 2021-01-07 22:32

Summary

XSS in HtmlSanitizer

Details

Impact

If you have explicitly allowed the <style> tag, an attacker could craft HTML that includes script after passing through the sanitizer. The default settings disallow the <style> tag so there is no risk if you have not explicitly allowed the <style> tag.

Patches

The problem has been fixed in version 5.0.372.

Workarounds

Remove the <style> tag from the set of allowed tags.

For more information

If you have any questions or comments about this advisory open an issue in https://github.com/mganss/HtmlSanitizer

Credits

This issue was discovered by Michal Bentkowski of Securitum.

Severity

6.1 (Medium)


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

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JSON

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{
  "affected": [
    {
      "package": {
        "ecosystem": "NuGet",
        "name": "HtmlSanitizer"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "5.0.372"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2020-26293"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-74",
      "CWE-79"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2021-01-04T18:21:52Z",
    "nvd_published_at": "2021-01-04T19:15:00Z",
    "severity": "LOW"
  },
  "details": "### Impact\n\nIf you have explicitly allowed the `\u003cstyle\u003e` tag, an attacker could craft HTML that includes script after passing through the sanitizer. The default settings disallow the `\u003cstyle\u003e` tag so there is no risk if you have not explicitly allowed the `\u003cstyle\u003e` tag.\n\n### Patches\n\nThe problem has been fixed in version 5.0.372.\n\n### Workarounds\n\nRemove the `\u003cstyle\u003e` tag from the set of allowed tags.\n\n### For more information\n\nIf you have any questions or comments about this advisory open an issue in https://github.com/mganss/HtmlSanitizer\n\n### Credits\n\nThis issue was discovered by Michal Bentkowski of Securitum.",
  "id": "GHSA-8j9v-h2vp-2hhv",
  "modified": "2021-01-07T22:32:04Z",
  "published": "2021-01-04T18:22:11Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/mganss/HtmlSanitizer/security/advisories/GHSA-8j9v-h2vp-2hhv"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-26293"
    },
    {
      "type": "WEB",
      "url": "https://github.com/mganss/HtmlSanitizer/commit/a3a7602a44d4155d51ec0fbbedc2a49e9c7e2eb8"
    },
    {
      "type": "WEB",
      "url": "https://github.com/mganss/HtmlSanitizer/releases/tag/v5.0.372"
    },
    {
      "type": "WEB",
      "url": "https://www.nuget.org/packages/HtmlSanitizer"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:N/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "XSS in HtmlSanitizer"
}

CVE-2020-26293 (GCVE-0-2020-26293)

Vulnerability from cvelistv5 – Published: 2021-01-04 18:20 – Updated: 2024-08-04 15:56

Title

Possible XSS bypass if style tag is allowed

Summary

HtmlSanitizer is a .NET library for cleaning HTML fragments and documents from constructs that can lead to XSS attacks. In HtmlSanitizer before version 5.0.372, there is a possible XSS bypass if style tag is allowed. If you have explicitly allowed the `<style>` tag, an attacker could craft HTML that includes script after passing through the sanitizer. The default settings disallow the `<style>` tag so there is no risk if you have not explicitly allowed the `<style>` tag. The problem has been fixed in version 5.0.372.

Severity

6.1 (Medium)


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

CWE

CWE-74 - Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

Assigner

GitHub_M mitre root

References

4 references

URL	Tags
https://github.com/mganss/HtmlSanitizer/security/…	x_refsource_CONFIRM
https://www.nuget.org/packages/HtmlSanitizer/	x_refsource_MISC
https://github.com/mganss/HtmlSanitizer/releases/…	x_refsource_MISC
https://github.com/mganss/HtmlSanitizer/commit/a3…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
mganss	HtmlSanitizer	Affected: < 5.0.372

Show details on NVD website

JSON

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          "dateUpdated": "2024-08-04T15:56:03.977Z",
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            "url": "https://github.com/mganss/HtmlSanitizer/commit/a3a7602a44d4155d51ec0fbbedc2a49e9c7e2eb8"
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            }
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        "affects": {
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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.