gsd-2023-32323
Vulnerability from gsd
Modified
2023-12-13 01:20
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.
Aliases
Aliases
{
"GSD": {
"alias": "CVE-2023-32323",
"id": "GSD-2023-32323"
},
"gsd": {
"metadata": {
"exploitCode": "unknown",
"remediation": "unknown",
"reportConfidence": "confirmed",
"type": "vulnerability"
},
"osvSchema": {
"aliases": [
"CVE-2023-32323"
],
"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.\n\n",
"id": "GSD-2023-32323",
"modified": "2023-12-13T01:20:23.408951Z",
"schema_version": "1.4.0"
}
},
"namespaces": {
"cve.org": {
"CVE_data_meta": {
"ASSIGNER": "security-advisories@github.com",
"ID": "CVE-2023-32323",
"STATE": "PUBLIC"
},
"affects": {
"vendor": {
"vendor_data": [
{
"product": {
"product_data": [
{
"product_name": "synapse",
"version": {
"version_data": [
{
"version_affected": "=",
"version_value": "\u003c 1.74.0"
}
]
}
}
]
},
"vendor_name": "matrix-org"
}
]
}
},
"data_format": "MITRE",
"data_type": "CVE",
"data_version": "4.0",
"description": {
"description_data": [
{
"lang": "eng",
"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.\n\n"
}
]
},
"impact": {
"cvss": [
{
"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"
}
]
},
"problemtype": {
"problemtype_data": [
{
"description": [
{
"cweId": "CWE-20",
"lang": "eng",
"value": "CWE-20: Improper Input Validation"
}
]
}
]
},
"references": {
"reference_data": [
{
"name": "https://github.com/matrix-org/synapse/security/advisories/GHSA-f3wc-3vxv-xmvr",
"refsource": "MISC",
"url": "https://github.com/matrix-org/synapse/security/advisories/GHSA-f3wc-3vxv-xmvr"
},
{
"name": "https://github.com/matrix-org/synapse/issues/14492",
"refsource": "MISC",
"url": "https://github.com/matrix-org/synapse/issues/14492"
},
{
"name": "https://github.com/matrix-org/synapse/pull/14642",
"refsource": "MISC",
"url": "https://github.com/matrix-org/synapse/pull/14642"
},
{
"name": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UJIJRP5ZH6B3KGFLHCAKR2IX2Y4Z25QD/",
"refsource": "MISC",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UJIJRP5ZH6B3KGFLHCAKR2IX2Y4Z25QD/"
}
]
},
"source": {
"advisory": "GHSA-f3wc-3vxv-xmvr",
"discovery": "UNKNOWN"
}
},
"gitlab.com": {
"advisories": [
{
"affected_range": "\u003c1.74.0",
"affected_versions": "All versions before 1.74.0",
"cvss_v3": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L",
"cwe_ids": [
"CWE-1035",
"CWE-20",
"CWE-937"
],
"date": "2023-06-02",
"description": "### Impact\n\nA 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.\n\nSynapse instances with federation disabled are not affected.\n\n#### Details\n\nThe Matrix protocol allows homeservers to provide an `invite_room_state` field on a [room invite](https://spec.matrix.org/v1.5/client-server-api/#mroommember) containing a [summary of room state](https://spec.matrix.org/v1.5/client-server-api/#stripped-state). In versions of Synapse up to and including v1.73.0, Synapse does not limit the size of `invite_room_state`, meaning that it was possible to create an arbitrarily large invite event.\n\nAn attacker with an account on a vulnerable Synapse homeserver X could exploit this by having X create an over-sized invite event in a room with a user from another homeserver Y. Once acknowledged by the invitee\u0027s homeserver, the invite event would be sent in a batch of events to Y. If the malicious invite is so large that the entire batch is rejected as too large, X\u0027s outgoing traffic to Y would become \"stuck\", meaning that messages and state events created by X would remain unseen by Y.\n\n### Patches\n\nSynapse 1.74 refuses to create oversized `invite_room_state` fields. Server operators should upgrade to Synapse 1.74 or newer urgently.\n\n### Workarounds\n\nThere are no robust workarounds.\n\nThis attack needs an account on Synapse homeserver X to deny federation from X to another homeserver Y. As a partial mitigation, Synapse operators can disable open registration to limit the ability of attackers to create new accounts on homeserver X.\n\nIf homeserver X has been attacked in this way, restarting it will resume outgoing federation by entering \"catchup mode\". For catchup mode to ignore the oversized invites, every attacked room must have a correctly-sized event sent by X which is newer than any oversized invite. This is difficult to arrange, and does not prevent the attacker from repeating their attack.\n\n### References\n\n- https://github.com/matrix-org/synapse/issues/14492 was caused by this issue.\n- https://github.com/matrix-org/synapse/issues/14642 includes the patch described above.\n\n### For more information\n\nIf you have any questions or comments about this advisory, e-mail us at [security@matrix.org](mailto:security@matrix.org).",
"fixed_versions": [
"1.74.0"
],
"identifier": "CVE-2023-32323",
"identifiers": [
"CVE-2023-32323",
"GHSA-f3wc-3vxv-xmvr"
],
"not_impacted": "All versions starting from 1.74.0",
"package_slug": "pypi/matrix-synapse",
"pubdate": "2023-05-26",
"solution": "Upgrade to version 1.74.0 or above.",
"title": "Synapse Outgoing federation to specific hosts can be disabled by sending malicious invites",
"urls": [
"https://github.com/matrix-org/synapse/security/advisories/GHSA-f3wc-3vxv-xmvr",
"https://github.com/matrix-org/synapse/issues/14492",
"https://github.com/matrix-org/synapse/pull/14642",
"https://github.com/advisories/GHSA-f3wc-3vxv-xmvr"
],
"uuid": "8396c4f6-65a5-4f05-b04a-d5fe94312bf8"
}
]
},
"nvd.nist.gov": {
"configurations": {
"CVE_data_version": "4.0",
"nodes": [
{
"children": [],
"cpe_match": [
{
"cpe23Uri": "cpe:2.3:a:matrix:synapse:*:*:*:*:*:*:*:*",
"cpe_name": [],
"versionEndExcluding": "1.74.0",
"vulnerable": true
}
],
"operator": "OR"
}
]
},
"cve": {
"CVE_data_meta": {
"ASSIGNER": "security-advisories@github.com",
"ID": "CVE-2023-32323"
},
"data_format": "MITRE",
"data_type": "CVE",
"data_version": "4.0",
"description": {
"description_data": [
{
"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.\n\n"
}
]
},
"problemtype": {
"problemtype_data": [
{
"description": [
{
"lang": "en",
"value": "CWE-20"
}
]
}
]
},
"references": {
"reference_data": [
{
"name": "https://github.com/matrix-org/synapse/security/advisories/GHSA-f3wc-3vxv-xmvr",
"refsource": "MISC",
"tags": [
"Mitigation",
"Vendor Advisory"
],
"url": "https://github.com/matrix-org/synapse/security/advisories/GHSA-f3wc-3vxv-xmvr"
},
{
"name": "https://github.com/matrix-org/synapse/pull/14642",
"refsource": "MISC",
"tags": [
"Patch"
],
"url": "https://github.com/matrix-org/synapse/pull/14642"
},
{
"name": "https://github.com/matrix-org/synapse/issues/14492",
"refsource": "MISC",
"tags": [
"Exploit",
"Issue Tracking"
],
"url": "https://github.com/matrix-org/synapse/issues/14492"
},
{
"name": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UJIJRP5ZH6B3KGFLHCAKR2IX2Y4Z25QD/",
"refsource": "MISC",
"tags": [],
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UJIJRP5ZH6B3KGFLHCAKR2IX2Y4Z25QD/"
}
]
}
},
"impact": {
"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": "2023-09-18T04:15Z",
"publishedDate": "2023-05-26T14:15Z"
}
}
}
Loading…
Loading…
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.