Vulnerability-Lookup

UBUNTU-CVE-2023-32323 (CVE-2023-32323)

Vulnerability from osv_ubuntu – Published: 2023-05-26 14:15 – Updated: 2025-09-08 16:56 – Source website

Details

Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. A malicious user on a Synapse homeserver X with permission to create certain state events can disable outbound federation from X to an arbitrary homeserver Y. Synapse instances with federation disabled are not affected. In versions of Synapse up to and including 1.73, Synapse did not limit the size of invite_room_state, meaning that it was possible to create an arbitrarily large invite event. Synapse 1.74 refuses to create oversized invite_room_state fields. Server operators should upgrade to Synapse 1.74 or newer urgently.

Severity

4.3 (Medium)


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

5.0 (Medium)


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

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2023-32323	REPORT
	https://github.com/matrix-org/synapse/security/ad…	REPORT
	https://github.com/matrix-org/synapse/pull/14642	REPORT
	https://github.com/matrix-org/synapse/issues/14492	REPORT
	https://www.cve.org/CVERecord?id=CVE-2023-32323	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "matrix-synapse",
            "binary_version": "0.24.0+dfsg-1ubuntu0.1~esm4"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:18.04:LTS",
        "name": "matrix-synapse",
        "purl": "pkg:deb/ubuntu/matrix-synapse@0.24.0+dfsg-1ubuntu0.1~esm4?arch=source\u0026distro=esm-apps/bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.19.2+dfsg-6",
        "0.24.0+dfsg-1",
        "0.24.0+dfsg-1ubuntu0.1~esm1",
        "0.24.0+dfsg-1ubuntu0.1~esm4"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "matrix-synapse",
            "binary_version": "1.11.0-1ubuntu0.1~esm2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:20.04:LTS",
        "name": "matrix-synapse",
        "purl": "pkg:deb/ubuntu/matrix-synapse@1.11.0-1ubuntu0.1~esm2?arch=source\u0026distro=esm-apps/focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.3.0-1",
        "1.4.0-1",
        "1.5.0-1",
        "1.5.1-1",
        "1.6.0-1",
        "1.6.1-1",
        "1.7.0-2",
        "1.7.1-1",
        "1.7.2-1",
        "1.7.3-1",
        "1.8.0-1",
        "1.9.0-1",
        "1.9.1-1",
        "1.10.0-1",
        "1.10.0-2",
        "1.11.0-1",
        "1.11.0-1ubuntu0.1~esm2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "matrix-synapse",
            "binary_version": "1.53.0-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "matrix-synapse",
        "purl": "pkg:deb/ubuntu/matrix-synapse@1.53.0-1?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.39.0-1",
        "1.47.0-2",
        "1.47.1-1",
        "1.48.0-1",
        "1.49.0-1",
        "1.49.2-1",
        "1.50.1-1",
        "1.50.2-1",
        "1.51.0-1",
        "1.52.0-1",
        "1.53.0-1"
      ]
    }
  ],
  "aliases": [],
  "details": "Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. A malicious user on a Synapse homeserver X with permission to create certain state events can disable outbound federation from X to an arbitrary homeserver Y. Synapse instances with federation disabled are not affected. In versions of Synapse up to and including 1.73, Synapse did not limit the size of `invite_room_state`, meaning that it was possible to create an arbitrarily large invite event. Synapse 1.74 refuses to create oversized `invite_room_state` fields. Server operators should upgrade to Synapse 1.74 or newer urgently.",
  "id": "UBUNTU-CVE-2023-32323",
  "modified": "2025-09-08T16:56:19Z",
  "published": "2023-05-26T14:15:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2023-32323"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/matrix-org/synapse/security/advisories/GHSA-f3wc-3vxv-xmvr"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/matrix-org/synapse/pull/14642"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/matrix-org/synapse/issues/14492"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2023-32323"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:L",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2023-32323"
  ]
}

CVE-2023-32323 (GCVE-0-2023-32323)

Vulnerability from cvelistv5 – Published: 2023-05-26 13:32 – Updated: 2025-02-13 16:50

Title

Synapse Outgoing federation to specific hosts can be disabled by sending malicious invites

Summary

Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. A malicious user on a Synapse homeserver X with permission to create certain state events can disable outbound federation from X to an arbitrary homeserver Y. Synapse instances with federation disabled are not affected. In versions of Synapse up to and including 1.73, Synapse did not limit the size of `invite_room_state`, meaning that it was possible to create an arbitrarily large invite event. Synapse 1.74 refuses to create oversized `invite_room_state` fields. Server operators should upgrade to Synapse 1.74 or newer urgently.

Severity

5 (Medium)


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

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2025-01-14 20:00 UTC

CWE

CWE-20 - Improper Input Validation

Assigner

GitHub_M mitre root

References

4 references

URL	Tags
https://github.com/matrix-org/synapse/security/ad…	x_refsource_CONFIRM
https://github.com/matrix-org/synapse/issues/14492	x_refsource_MISC
https://github.com/matrix-org/synapse/pull/14642	x_refsource_MISC
https://lists.fedoraproject.org/archives/list/pac…

Impacted products

1 product

Vendor	Product	Version
matrix-org	synapse	Affected: < 1.74.0

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-02T15:10:24.899Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
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        },
        "references": [
          {
            "name": "https://github.com/matrix-org/synapse/security/advisories/GHSA-f3wc-3vxv-xmvr",
            "tags": [
              "x_refsource_CONFIRM",
              "x_transferred"
            ],
            "url": "https://github.com/matrix-org/synapse/security/advisories/GHSA-f3wc-3vxv-xmvr"
          },
          {
            "name": "https://github.com/matrix-org/synapse/issues/14492",
            "tags": [
              "x_refsource_MISC",
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            ],
            "url": "https://github.com/matrix-org/synapse/issues/14492"
          },
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            "name": "https://github.com/matrix-org/synapse/pull/14642",
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            ],
            "url": "https://github.com/matrix-org/synapse/pull/14642"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UJIJRP5ZH6B3KGFLHCAKR2IX2Y4Z25QD/"
          }
        ],
        "title": "CVE Program Container"
      },
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2023-32323",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-01-14T20:00:17.125564Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
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        ],
        "providerMetadata": {
          "dateUpdated": "2025-01-14T20:00:25.608Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "synapse",
          "vendor": "matrix-org",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 1.74.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. A malicious user on a Synapse homeserver X with permission to create certain state events can disable outbound federation from X to an arbitrary homeserver Y. Synapse instances with federation disabled are not affected. In versions of Synapse up to and including 1.73, Synapse did not limit the size of `invite_room_state`, meaning that it was possible to create an arbitrarily large invite event. Synapse 1.74 refuses to create oversized `invite_room_state` fields. Server operators should upgrade to Synapse 1.74 or newer urgently."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "LOW",
            "baseScore": 5,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:L",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-20",
              "description": "CWE-20: Improper Input Validation",
              "lang": "en",
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            }
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      "providerMetadata": {
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      },
      "references": [
        {
          "name": "https://github.com/matrix-org/synapse/security/advisories/GHSA-f3wc-3vxv-xmvr",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/matrix-org/synapse/security/advisories/GHSA-f3wc-3vxv-xmvr"
        },
        {
          "name": "https://github.com/matrix-org/synapse/issues/14492",
          "tags": [
            "x_refsource_MISC"
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          "url": "https://github.com/matrix-org/synapse/issues/14492"
        },
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          "tags": [
            "x_refsource_MISC"
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          "url": "https://github.com/matrix-org/synapse/pull/14642"
        },
        {
          "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UJIJRP5ZH6B3KGFLHCAKR2IX2Y4Z25QD/"
        }
      ],
      "source": {
        "advisory": "GHSA-f3wc-3vxv-xmvr",
        "discovery": "UNKNOWN"
      },
      "title": "Synapse Outgoing federation to specific hosts can be disabled by sending malicious invites"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2023-32323",
    "datePublished": "2023-05-26T13:32:01.632Z",
    "dateReserved": "2023-05-08T13:26:03.880Z",
    "dateUpdated": "2025-02-13T16:50:32.310Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1"
}

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.