GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

GSD-2021-43827

Vulnerability from gsd - Updated: 2023-12-13 01:23
Details
discourse-footnote is a library providing footnotes for posts in Discourse. ### Impact When posting an inline footnote wrapped in `<a>` tags (e.g. `<a>^[footnote]</a>`, the resulting rendered HTML would include a nested `<a>`, which is stripped by Nokogiri because it is not valid. This then caused a javascript error on topic pages because we were looking for an `<a>` element inside the footnote reference span and getting its ID, and because it did not exist we got a null reference error in javascript. Users are advised to update to version 0.2. As a workaround editing offending posts from the rails console or the database console for self-hosters, or disabling the plugin in the admin panel can mitigate this issue.
Aliases
Aliases

{
  "GSD": {
    "alias": "CVE-2021-43827",
    "description": "discourse-footnote is a library providing footnotes for posts in Discourse. ### Impact When posting an inline footnote wrapped in `\u003ca\u003e` tags (e.g. `\u003ca\u003e^[footnote]\u003c/a\u003e`, the resulting rendered HTML would include a nested `\u003ca\u003e`, which is stripped by Nokogiri because it is not valid. This then caused a javascript error on topic pages because we were looking for an `\u003ca\u003e` element inside the footnote reference span and getting its ID, and because it did not exist we got a null reference error in javascript. Users are advised to update to version 0.2. As a workaround editing offending posts from the rails console or the database console for self-hosters, or disabling the plugin in the admin panel can mitigate this issue.",
    "id": "GSD-2021-43827"
  },
  "gsd": {
    "metadata": {
      "exploitCode": "unknown",
      "remediation": "unknown",
      "reportConfidence": "confirmed",
      "type": "vulnerability"
    },
    "osvSchema": {
      "aliases": [
        "CVE-2021-43827"
      ],
      "details": "discourse-footnote is a library providing footnotes for posts in Discourse. ### Impact When posting an inline footnote wrapped in `\u003ca\u003e` tags (e.g. `\u003ca\u003e^[footnote]\u003c/a\u003e`, the resulting rendered HTML would include a nested `\u003ca\u003e`, which is stripped by Nokogiri because it is not valid. This then caused a javascript error on topic pages because we were looking for an `\u003ca\u003e` element inside the footnote reference span and getting its ID, and because it did not exist we got a null reference error in javascript. Users are advised to update to version 0.2. As a workaround editing offending posts from the rails console or the database console for self-hosters, or disabling the plugin in the admin panel can mitigate this issue.",
      "id": "GSD-2021-43827",
      "modified": "2023-12-13T01:23:26.695093Z",
      "schema_version": "1.4.0"
    }
  },
  "namespaces": {
    "cve.org": {
      "CVE_data_meta": {
        "ASSIGNER": "security-advisories@github.com",
        "ID": "CVE-2021-43827",
        "STATE": "PUBLIC",
        "TITLE": "Inline footnotes wrapped in \u003ca\u003e tags can cause errors in discourse-footnotes"
      },
      "affects": {
        "vendor": {
          "vendor_data": [
            {
              "product": {
                "product_data": [
                  {
                    "product_name": "discourse-footnote",
                    "version": {
                      "version_data": [
                        {
                          "version_value": "\u003c 0.2"
                        }
                      ]
                    }
                  }
                ]
              },
              "vendor_name": "discourse"
            }
          ]
        }
      },
      "data_format": "MITRE",
      "data_type": "CVE",
      "data_version": "4.0",
      "description": {
        "description_data": [
          {
            "lang": "eng",
            "value": "discourse-footnote is a library providing footnotes for posts in Discourse. ### Impact When posting an inline footnote wrapped in `\u003ca\u003e` tags (e.g. `\u003ca\u003e^[footnote]\u003c/a\u003e`, the resulting rendered HTML would include a nested `\u003ca\u003e`, which is stripped by Nokogiri because it is not valid. This then caused a javascript error on topic pages because we were looking for an `\u003ca\u003e` element inside the footnote reference span and getting its ID, and because it did not exist we got a null reference error in javascript. Users are advised to update to version 0.2. As a workaround editing offending posts from the rails console or the database console for self-hosters, or disabling the plugin in the admin panel can mitigate this issue."
          }
        ]
      },
      "impact": {
        "cvss": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "LOW",
          "baseScore": 4.3,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L",
          "version": "3.1"
        }
      },
      "problemtype": {
        "problemtype_data": [
          {
            "description": [
              {
                "lang": "eng",
                "value": "CWE-755: Improper Handling of Exceptional Conditions"
              }
            ]
          }
        ]
      },
      "references": {
        "reference_data": [
          {
            "name": "https://github.com/discourse/discourse-footnote/security/advisories/GHSA-58vr-c56v-qr57",
            "refsource": "CONFIRM",
            "url": "https://github.com/discourse/discourse-footnote/security/advisories/GHSA-58vr-c56v-qr57"
          },
          {
            "name": "https://github.com/discourse/discourse-footnote/commit/796617e0131277011207541313522cd1946661ab",
            "refsource": "MISC",
            "url": "https://github.com/discourse/discourse-footnote/commit/796617e0131277011207541313522cd1946661ab"
          }
        ]
      },
      "source": {
        "advisory": "GHSA-58vr-c56v-qr57",
        "discovery": "UNKNOWN"
      }
    },
    "nvd.nist.gov": {
      "configurations": {
        "CVE_data_version": "4.0",
        "nodes": [
          {
            "children": [],
            "cpe_match": [
              {
                "cpe23Uri": "cpe:2.3:a:discourse:discourse_footnote:*:*:*:*:*:discourse:*:*",
                "cpe_name": [],
                "versionEndExcluding": "0.2",
                "vulnerable": true
              }
            ],
            "operator": "OR"
          }
        ]
      },
      "cve": {
        "CVE_data_meta": {
          "ASSIGNER": "security-advisories@github.com",
          "ID": "CVE-2021-43827"
        },
        "data_format": "MITRE",
        "data_type": "CVE",
        "data_version": "4.0",
        "description": {
          "description_data": [
            {
              "lang": "en",
              "value": "discourse-footnote is a library providing footnotes for posts in Discourse. ### Impact When posting an inline footnote wrapped in `\u003ca\u003e` tags (e.g. `\u003ca\u003e^[footnote]\u003c/a\u003e`, the resulting rendered HTML would include a nested `\u003ca\u003e`, which is stripped by Nokogiri because it is not valid. This then caused a javascript error on topic pages because we were looking for an `\u003ca\u003e` element inside the footnote reference span and getting its ID, and because it did not exist we got a null reference error in javascript. Users are advised to update to version 0.2. As a workaround editing offending posts from the rails console or the database console for self-hosters, or disabling the plugin in the admin panel can mitigate this issue."
            }
          ]
        },
        "problemtype": {
          "problemtype_data": [
            {
              "description": [
                {
                  "lang": "en",
                  "value": "CWE-755"
                }
              ]
            }
          ]
        },
        "references": {
          "reference_data": [
            {
              "name": "https://github.com/discourse/discourse-footnote/commit/796617e0131277011207541313522cd1946661ab",
              "refsource": "MISC",
              "tags": [
                "Patch",
                "Third Party Advisory"
              ],
              "url": "https://github.com/discourse/discourse-footnote/commit/796617e0131277011207541313522cd1946661ab"
            },
            {
              "name": "https://github.com/discourse/discourse-footnote/security/advisories/GHSA-58vr-c56v-qr57",
              "refsource": "CONFIRM",
              "tags": [
                "Third Party Advisory"
              ],
              "url": "https://github.com/discourse/discourse-footnote/security/advisories/GHSA-58vr-c56v-qr57"
            }
          ]
        }
      },
      "impact": {
        "baseMetricV2": {
          "acInsufInfo": false,
          "cvssV2": {
            "accessComplexity": "LOW",
            "accessVector": "NETWORK",
            "authentication": "SINGLE",
            "availabilityImpact": "PARTIAL",
            "baseScore": 4.0,
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "vectorString": "AV:N/AC:L/Au:S/C:N/I:N/A:P",
            "version": "2.0"
          },
          "exploitabilityScore": 8.0,
          "impactScore": 2.9,
          "obtainAllPrivilege": false,
          "obtainOtherPrivilege": false,
          "obtainUserPrivilege": false,
          "severity": "MEDIUM",
          "userInteractionRequired": false
        },
        "baseMetricV3": {
          "cvssV3": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "LOW",
            "baseScore": 4.3,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L",
            "version": "3.1"
          },
          "exploitabilityScore": 2.8,
          "impactScore": 1.4
        }
      },
      "lastModifiedDate": "2021-12-29T20:31Z",
      "publishedDate": "2021-12-14T23:15Z"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.


Loading…

Loading…

Loading…

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.

Loading…

Detection rules are retrieved from Rulezet.

Loading…

Loading…

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.


Loading…