Vulnerability-Lookup

CVE-2021-40823 (GCVE-0-2021-40823)

Vulnerability from cvelistv5 – Published: 2021-09-13 18:45 – Updated: 2024-08-04 02:51

Summary

A logic error in the room key sharing functionality of matrix-js-sdk (aka Matrix Javascript SDK) before 12.4.1 allows a malicious Matrix homeserver present in an encrypted room to steal room encryption keys (via crafted Matrix protocol messages) that were originally sent by affected Matrix clients participating in that room. This allows the homeserver to decrypt end-to-end encrypted messages sent by affected clients.

Severity

5.9 (Medium)


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

CWE

Assigner

mitre CNA under the mitre root

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

References

2 references

URL	Tags
https://github.com/matrix-org/matrix-js-sdk/relea…	x_refsource_MISC
https://matrix.org/blog/2021/09/13/vulnerability-…	x_refsource_MISC

Show details on NVD website

JSON

To clipboard

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CLEANSTART-2024-FT51773 (CVE-2021-40823)

Vulnerability from cleanstart – Published: 2026-10-01 07:32 – Updated: 2026-10-08 14:25 – Source website

Summary

logic error in the room key sharing functionality of matrix-js-sdk (aka Matrix Javascript SDK) before 12

Details

Security vulnerability affects the element-web package. A logic error in the room key sharing functionality of matrix-js-sdk (aka Matrix Javascript SDK) before 12.

Severity

5.9 (Medium)


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

References

URL

Type

	https://github.com/cleanstart-dev/cleanstart-secu…	ADVISORY
	https://osv.dev/vulnerability/CVE-2021-40823	WEB
	https://nvd.nist.gov/vuln/detail/CVE-2021-40823	WEB

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "CleanStart",
        "name": "element-web",
        "purl": "pkg:apk/cleanstart/element-web?arch=noarch"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.8.4-r0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "credits": [],
  "database_specific": {},
  "details": "Security vulnerability affects the element-web package. A logic error in the room key sharing functionality of matrix-js-sdk (aka Matrix Javascript SDK) before 12.",
  "id": "CLEANSTART-2024-FT51773",
  "modified": "2026-10-08T14:25:04Z",
  "published": "2026-10-01T07:32:21.645848Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/cleanstart-dev/cleanstart-security-advisories/tree/main/advisories/2024/CLEANSTART-2024-FT51773.json"
    },
    {
      "type": "WEB",
      "url": "https://osv.dev/vulnerability/CVE-2021-40823"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-40823"
    }
  ],
  "related": [],
  "schema_version": "1.7.3",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "logic error in the room key sharing functionality of matrix-js-sdk (aka Matrix Javascript SDK) before 12",
  "upstream": [
    "CVE-2021-40823"
  ]
}

FKIE_CVE-2021-40823

Vulnerability from fkie_nvd - Published: 2021-09-13 19:15 - Updated: 2026-06-17 04:07

Severity

5.9 (Medium) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

Summary

References

URL	Tags
cve@mitre.org	https://github.com/matrix-org/matrix-js-sdk/releases/tag/v12.4.1	Third Party Advisory
cve@mitre.org	https://matrix.org/blog/2021/09/13/vulnerability-disclosure-key-sharing	Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108	https://github.com/matrix-org/matrix-js-sdk/releases/tag/v12.4.1	Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108	https://matrix.org/blog/2021/09/13/vulnerability-disclosure-key-sharing	Vendor Advisory

Impacted products

	Vendor	Product	Version
	matrix	javascript_sdk	*

JSON

To clipboard

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        {
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        "Third Party Advisory"
      ],
      "url": "https://github.com/matrix-org/matrix-js-sdk/releases/tag/v12.4.1"
    },
    {
      "source": "cve@mitre.org",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://matrix.org/blog/2021/09/13/vulnerability-disclosure-key-sharing"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://github.com/matrix-org/matrix-js-sdk/releases/tag/v12.4.1"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://matrix.org/blog/2021/09/13/vulnerability-disclosure-key-sharing"
    }
  ],
  "sourceIdentifier": "cve@mitre.org",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-290"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}

GHSA-23CM-X6J7-6HQ3

Vulnerability from github – Published: 2021-09-14 20:24 – Updated: 2023-08-08 19:58

Summary

matrix-js-sdk can be tricked into disclosing E2EE room keys to a participating homeserver

Details

Impact

A logic error in the room key sharing functionality of matrix-js-sdk before 12.4.1 allows a malicious Matrix homeserver† participating in an encrypted room to steal room encryption keys from affected Matrix clients participating in that room. This allows the homeserver to decrypt end-to-end encrypted messages sent by affected clients.

† Or anyone with access to the account of the original recipient of an encrypted message.

Known clients affected (via their use of vulnerable versions of matrix-js-sdk):

Element Web (1.8.2 and earlier)
Element Desktop (1.8.2 and earlier)
SchildiChat Web (1.7.32-sc1 and earlier)
SchildiChat Desktop (1.7.32-sc1 and earlier)
Cinny (1.2.0 and earlier)

Patch

This was fixed in https://github.com/matrix-org/matrix-js-sdk/commit/894c24880da0e1cc81818f51c0db80e3c9fb2be9.

Workarounds

To prevent a homeserver from being able to steal the room keys, vulnerable clients can be taken offline or signed out. If signing out, care should be taken to either set up Secure Backup or export E2E room keys in order to preserve access to past messages.

Severity

5.9 (Medium)


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

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "matrix-js-sdk"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "12.4.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2021-40823"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-200",
      "CWE-327"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2021-09-14T18:08:41Z",
    "nvd_published_at": "2021-09-13T19:15:00Z",
    "severity": "MODERATE"
  },
  "details": "### Impact\n\nA logic error in the room key sharing functionality of matrix-js-sdk before 12.4.1 allows a malicious Matrix homeserver\u2020 participating in an encrypted room to steal room encryption keys from affected Matrix clients participating in that room. This allows the homeserver to decrypt end-to-end encrypted messages sent by affected clients.\n\n\u2020 Or anyone with access to the account of the original recipient of an encrypted message.\n\nKnown clients affected (via their use of vulnerable versions of matrix-js-sdk):\n\n- Element Web (1.8.2 and earlier)\n- Element Desktop (1.8.2 and earlier)\n- SchildiChat Web (1.7.32-sc1 and earlier)\n- SchildiChat Desktop (1.7.32-sc1 and earlier)\n- Cinny (1.2.0 and earlier)\n\n### Patch\n\nThis was fixed in https://github.com/matrix-org/matrix-js-sdk/commit/894c24880da0e1cc81818f51c0db80e3c9fb2be9.\n\n### Workarounds\nTo prevent a homeserver from being able to steal the room keys, vulnerable clients can be taken offline or signed out. If signing out, care should be taken to either set up Secure Backup or export E2E room keys in order to preserve access to past messages.",
  "id": "GHSA-23cm-x6j7-6hq3",
  "modified": "2023-08-08T19:58:08Z",
  "published": "2021-09-14T20:24:18Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/matrix-org/matrix-js-sdk/security/advisories/GHSA-23cm-x6j7-6hq3"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-40823"
    },
    {
      "type": "WEB",
      "url": "https://github.com/matrix-org/matrix-js-sdk/commit/894c24880da0e1cc81818f51c0db80e3c9fb2be9"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/matrix-org/matrix-js-sdk"
    },
    {
      "type": "WEB",
      "url": "https://github.com/matrix-org/matrix-js-sdk/releases/tag/v12.4.1"
    },
    {
      "type": "WEB",
      "url": "https://matrix.org/blog/2021/09/13/vulnerability-disclosure-key-sharing"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "matrix-js-sdk can be tricked into disclosing E2EE room keys to a participating homeserver"
}

GSD-2021-40823

Vulnerability from gsd - Updated: 2023-12-13 01:23

Details

Aliases

CVE-2021-40823

Aliases

CVE-2021-40823

JSON

To clipboard

{
  "GSD": {
    "alias": "CVE-2021-40823",
    "description": "A logic error in the room key sharing functionality of matrix-js-sdk (aka Matrix Javascript SDK) before 12.4.1 allows a malicious Matrix homeserver present in an encrypted room to steal room encryption keys (via crafted Matrix protocol messages) that were originally sent by affected Matrix clients participating in that room. This allows the homeserver to decrypt end-to-end encrypted messages sent by affected clients.",
    "id": "GSD-2021-40823",
    "references": [
      "https://security.archlinux.org/CVE-2021-40823"
    ]
  },
  "gsd": {
    "metadata": {
      "exploitCode": "unknown",
      "remediation": "unknown",
      "reportConfidence": "confirmed",
      "type": "vulnerability"
    },
    "osvSchema": {
      "aliases": [
        "CVE-2021-40823"
      ],
      "details": "A logic error in the room key sharing functionality of matrix-js-sdk (aka Matrix Javascript SDK) before 12.4.1 allows a malicious Matrix homeserver present in an encrypted room to steal room encryption keys (via crafted Matrix protocol messages) that were originally sent by affected Matrix clients participating in that room. This allows the homeserver to decrypt end-to-end encrypted messages sent by affected clients.",
      "id": "GSD-2021-40823",
      "modified": "2023-12-13T01:23:25.174886Z",
      "schema_version": "1.4.0"
    }
  },
  "namespaces": {
    "cve.org": {
      "CVE_data_meta": {
        "ASSIGNER": "cve@mitre.org",
        "ID": "CVE-2021-40823",
        "STATE": "PUBLIC"
      },
      "affects": {
        "vendor": {
          "vendor_data": [
            {
              "product": {
                "product_data": [
                  {
                    "product_name": "n/a",
                    "version": {
                      "version_data": [
                        {
                          "version_value": "n/a"
                        }
                      ]
                    }
                  }
                ]
              },
              "vendor_name": "n/a"
            }
          ]
        }
      },
      "data_format": "MITRE",
      "data_type": "CVE",
      "data_version": "4.0",
      "description": {
        "description_data": [
          {
            "lang": "eng",
            "value": "A logic error in the room key sharing functionality of matrix-js-sdk (aka Matrix Javascript SDK) before 12.4.1 allows a malicious Matrix homeserver present in an encrypted room to steal room encryption keys (via crafted Matrix protocol messages) that were originally sent by affected Matrix clients participating in that room. This allows the homeserver to decrypt end-to-end encrypted messages sent by affected clients."
          }
        ]
      },
      "problemtype": {
        "problemtype_data": [
          {
            "description": [
              {
                "lang": "eng",
                "value": "n/a"
              }
            ]
          }
        ]
      },
      "references": {
        "reference_data": [
          {
            "name": "https://github.com/matrix-org/matrix-js-sdk/releases/tag/v12.4.1",
            "refsource": "MISC",
            "url": "https://github.com/matrix-org/matrix-js-sdk/releases/tag/v12.4.1"
          },
          {
            "name": "https://matrix.org/blog/2021/09/13/vulnerability-disclosure-key-sharing",
            "refsource": "MISC",
            "url": "https://matrix.org/blog/2021/09/13/vulnerability-disclosure-key-sharing"
          }
        ]
      }
    },
    "gitlab.com": {
      "advisories": [
        {
          "affected_range": "\u003c12.4.1",
          "affected_versions": "All versions before 12.4.1",
          "cvss_v2": "AV:N/AC:M/Au:N/C:P/I:N/A:N",
          "cvss_v3": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
          "cwe_ids": [
            "CWE-1035",
            "CWE-290",
            "CWE-937"
          ],
          "date": "2023-08-08",
          "description": "There is a logic error in the room key sharing functionality of matrix-js-sdk (aka Matrix Javascript SDK). This allows the homeserver to decrypt end-to-end encrypted messages sent by affected clients.",
          "fixed_versions": [
            "12.4.1"
          ],
          "identifier": "CVE-2021-40823",
          "identifiers": [
            "CVE-2021-40823"
          ],
          "not_impacted": "All versions starting from 12.4.1",
          "package_slug": "npm/matrix-js-sdk",
          "pubdate": "2021-09-13",
          "solution": "Upgrade to version 12.4.1 or above.",
          "title": "Use of a Broken or Risky Cryptographic Algorithm",
          "urls": [
            "https://nvd.nist.gov/vuln/detail/CVE-2021-40823",
            "https://matrix.org/blog/2021/09/13/vulnerability-disclosure-key-sharing"
          ],
          "uuid": "9ebb84bb-f7fd-40fa-9dd2-b43568919140"
        }
      ]
    },
    "nvd.nist.gov": {
      "configurations": {
        "CVE_data_version": "4.0",
        "nodes": [
          {
            "children": [],
            "cpe_match": [
              {
                "cpe23Uri": "cpe:2.3:a:matrix:javascript_sdk:*:*:*:*:*:*:*:*",
                "cpe_name": [],
                "versionEndExcluding": "12.4.1",
                "vulnerable": true
              }
            ],
            "operator": "OR"
          }
        ]
      },
      "cve": {
        "CVE_data_meta": {
          "ASSIGNER": "cve@mitre.org",
          "ID": "CVE-2021-40823"
        },
        "data_format": "MITRE",
        "data_type": "CVE",
        "data_version": "4.0",
        "description": {
          "description_data": [
            {
              "lang": "en",
              "value": "A logic error in the room key sharing functionality of matrix-js-sdk (aka Matrix Javascript SDK) before 12.4.1 allows a malicious Matrix homeserver present in an encrypted room to steal room encryption keys (via crafted Matrix protocol messages) that were originally sent by affected Matrix clients participating in that room. This allows the homeserver to decrypt end-to-end encrypted messages sent by affected clients."
            }
          ]
        },
        "problemtype": {
          "problemtype_data": [
            {
              "description": [
                {
                  "lang": "en",
                  "value": "CWE-327"
                }
              ]
            }
          ]
        },
        "references": {
          "reference_data": [
            {
              "name": "https://github.com/matrix-org/matrix-js-sdk/releases/tag/v12.4.1",
              "refsource": "MISC",
              "tags": [
                "Third Party Advisory"
              ],
              "url": "https://github.com/matrix-org/matrix-js-sdk/releases/tag/v12.4.1"
            },
            {
              "name": "https://matrix.org/blog/2021/09/13/vulnerability-disclosure-key-sharing",
              "refsource": "MISC",
              "tags": [
                "Vendor Advisory"
              ],
              "url": "https://matrix.org/blog/2021/09/13/vulnerability-disclosure-key-sharing"
            }
          ]
        }
      },
      "impact": {
        "baseMetricV2": {
          "acInsufInfo": false,
          "cvssV2": {
            "accessComplexity": "MEDIUM",
            "accessVector": "NETWORK",
            "authentication": "NONE",
            "availabilityImpact": "NONE",
            "baseScore": 4.3,
            "confidentialityImpact": "PARTIAL",
            "integrityImpact": "NONE",
            "vectorString": "AV:N/AC:M/Au:N/C:P/I:N/A:N",
            "version": "2.0"
          },
          "exploitabilityScore": 8.6,
          "impactScore": 2.9,
          "obtainAllPrivilege": false,
          "obtainOtherPrivilege": false,
          "obtainUserPrivilege": false,
          "severity": "MEDIUM",
          "userInteractionRequired": false
        },
        "baseMetricV3": {
          "cvssV3": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 5.9,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
            "version": "3.1"
          },
          "exploitabilityScore": 2.2,
          "impactScore": 3.6
        }
      },
      "lastModifiedDate": "2021-09-24T17:27Z",
      "publishedDate": "2021-09-13T19:15Z"
    }
  }
}

UBUNTU-CVE-2021-40823 (CVE-2021-40823)

Vulnerability from osv_ubuntu – Published: 2021-09-13 19:15 – Updated: 2025-10-24 04:50 – Source website

Details

Severity

5.9 (Medium)


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

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2021-40823	REPORT
	https://matrix.org/blog/2021/09/13/vulnerability-…	REPORT
	https://github.com/matrix-org/matrix-js-sdk/commi…	REPORT
	https://github.com/matrix-org/matrix-js-sdk/relea…	REPORT
	https://matrix.org/blog/2021/09/13/vulnerability-…	REPORT
	https://www.cve.org/CVERecord?id=CVE-2021-40823	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libjs-matrix-js-sdk",
            "binary_version": "0.9.2-1"
          },
          {
            "binary_name": "node-matrix-js-sdk",
            "binary_version": "0.9.2-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "node-matrix-js-sdk",
        "purl": "pkg:deb/ubuntu/node-matrix-js-sdk@0.9.2-1?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.9.2-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libjs-matrix-js-sdk",
            "binary_version": "9.11.0+~cs9.9.16-1"
          },
          {
            "binary_name": "node-matrix-js-sdk",
            "binary_version": "9.11.0+~cs9.9.16-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "node-matrix-js-sdk",
        "purl": "pkg:deb/ubuntu/node-matrix-js-sdk@9.11.0+~cs9.9.16-1?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "9.3.0+~cs9.9.16-2",
        "9.11.0+~cs9.9.16-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libjs-matrix-js-sdk",
            "binary_version": "9.11.0+~cs9.9.16-2"
          },
          {
            "binary_name": "node-matrix-js-sdk",
            "binary_version": "9.11.0+~cs9.9.16-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "node-matrix-js-sdk",
        "purl": "pkg:deb/ubuntu/node-matrix-js-sdk@9.11.0+~cs9.9.16-2?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "9.11.0+~cs9.9.16-2"
      ]
    }
  ],
  "aliases": [],
  "details": "A logic error in the room key sharing functionality of matrix-js-sdk (aka Matrix Javascript SDK) before 12.4.1 allows a malicious Matrix homeserver present in an encrypted room to steal room encryption keys (via crafted Matrix protocol messages) that were originally sent by affected Matrix clients participating in that room. This allows the homeserver to decrypt end-to-end encrypted messages sent by affected clients.",
  "id": "UBUNTU-CVE-2021-40823",
  "modified": "2025-10-24T04:50:34Z",
  "published": "2021-09-13T19:15:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-40823"
    },
    {
      "type": "REPORT",
      "url": "https://matrix.org/blog/2021/09/13/vulnerability-disclosure-key-sharing/"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/matrix-org/matrix-js-sdk/commit/894c24880da0e1cc81818f51c0db80e3c9fb2be9"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/matrix-org/matrix-js-sdk/releases/tag/v12.4.1"
    },
    {
      "type": "REPORT",
      "url": "https://matrix.org/blog/2021/09/13/vulnerability-disclosure-key-sharing"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2021-40823"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2021-40823"
  ]
}

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.

Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

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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.
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.

Action not permitted

CVE-2021-40823 (GCVE-0-2021-40823)

CLEANSTART-2024-FT51773 (CVE-2021-40823)

FKIE_CVE-2021-40823

GHSA-23CM-X6J7-6HQ3

Impact

Patch

Workarounds

GSD-2021-40823

UBUNTU-CVE-2021-40823 (CVE-2021-40823)

Tags

Sightings

Nomenclature

Vulnerability timeline

Related by attack behaviour