High
Mastodon vulnerable to Denial of Service through slow HTTP responses
Type: advisorySources: OSV
Mastodon is a free, open-source social network server based on ActivityPub. When performing outgoing HTTP queries, Mastodon sets a timeout on individual read operations. Prior to versions 3.5.9, 4.0.5, and 4.1.3, a malicious server can indefinitely extend the duration of the response through slowloris-type attacks. This vulnerability can be used to keep all Mastodon workers busy for an extended duration of time, leading to the server becoming unresponsive. Versions 3.5.9, 4.0.5, and 4.1.3 contain a patch for this issue.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2023-36461
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 8 Nov 2026, 03:11 UTC · Revision 1
Source evidence
Mastodon vulnerable to Denial of Service through slow HTTP responses
core-osv · Original sourcePublished 6 Jul 2023, 18:57 UTC
Mastodon is a free, open-source social network server based on ActivityPub. When performing outgoing HTTP queries, Mastodon sets a timeout on individual read operations. Prior to versions 3.5.9, 4.0.5, and 4.1.3, a malicious server can indefinitely extend the duration of the response through slowloris-type attacks. This vulnerability can be used to keep all Mastodon workers busy for an extended duration of time, leading to the server becoming unresponsive. Versions 3.5.9, 4.0.5, and 4.1.3 contain a patch for this issue.
osv:CVE-2023-36461
Complete source record
{
"id": "5b306dbe2972d9d64f13722697f36b967ffd2cea47cc6460c1bf618ca91882a8",
"url": "https://osv.dev/vulnerability/CVE-2023-36461",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "Mastodon vulnerable to Denial of Service through slow HTTP responses",
"summary": "Mastodon is a free, open-source social network server based on ActivityPub. When performing outgoing HTTP queries, Mastodon sets a timeout on individual read operations. Prior to versions 3.5.9, 4.0.5, and 4.1.3, a malicious server can indefinitely extend the duration of the response through slowloris-type attacks. This vulnerability can be used to keep all Mastodon workers busy for an extended duration of time, leading to the server becoming unresponsive. Versions 3.5.9, 4.0.5, and 4.1.3 contain a patch for this issue.",
"evidence": "osv:CVE-2023-36461",
"products": [],
"severity": "high",
"structured": {
"id": "CVE-2023-36461",
"aliases": [
"BIT-mastodon-2023-36461",
"CVE-2023-36461",
"GHSA-9pxv-6qvf-pjwc"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/mastodon/mastodon",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "b10c974ba1952c545acff505bfd36feb0c60b000"
},
{
"introduced": "fb389bd73c8a4bc2924496f6041c8eee27572d21"
},
{
"fixed": "8d7f6550f91338fb69e5c6e0cd28653122784665"
},
{
"introduced": "61c5dfb9295ea66c376c452a7ef7379e8c562416"
},
{
"fixed": "0d5781ca7609590a6d5340bb685bb1804056bb46"
},
{
"fixed": "c5929798bf7e56cc2c79b15bed0c4692ded3dcb6"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:joinmastodon:mastodon:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"fixed": "3.5.9"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:joinmastodon:mastodon:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "4.0.0"
},
{
"fixed": "4.0.5"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:joinmastodon:mastodon:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "4.1.0"
},
{
"fixed": "4.1.3"
}
],
"source": "CPE_RANGE"
},
{
"range": [
{
"fixed": "c5929798bf7e56cc2c79b15bed0c4692ded3dcb6"
}
],
"source": "REFERENCES_COMMIT"
},
{
"range": [
{
"fixed": "b10c974ba1952c545acff505bfd36feb0c60b000"
}
],
"source": "REFERENCES_TAG",
"original_tag": "v3.5.9"
},
{
"range": [
{
"fixed": "8d7f6550f91338fb69e5c6e0cd28653122784665"
}
],
"source": "REFERENCES_TAG",
"original_tag": "v4.0.5"
},
{
"range": [
{
"fixed": "0d5781ca7609590a6d5340bb685bb1804056bb46"
}
],
"source": "REFERENCES_TAG",
"original_tag": "v4.1.3"
}
]
}
}
],
"versions": [
"v3.5.8",
"v4.0.4",
"v4.1.2",
"v4.1.1",
"v4.0.3",
"v3.5.7",
"v3.5.6",
"v4.0.2",
"v4.1.0",
"v3.5.5",
"v4.0.1",
"v3.5.4",
"v4.0.0",
"v3.5.3",
"v3.5.2",
"v3.5.1",
"v3.5.0",
"v3.5.0rc3",
"v3.5.0rc2",
"v3.5.0rc1",
"v3.3.0",
"v3.4.1",
"v3.4.0",
"v3.4.0rc2",
"v3.4.0rc1",
"v3.3.0rc3",
"v3.3.0rc2",
"v3.3.0rc1",
"v3.2.0",
"v3.2.0rc2",
"v3.2.0rc1",
"v3.1.4",
"v3.1.3",
"v3.1.2",
"v3.0.1",
"v3.1.1",
"v3.1.0",
"v3.1.0rc2",
"v3.1.0rc1",
"v3.0.0",
"v3.0.0rc3",
"v3.0.0rc2",
"v3.0.0rc1",
"v2.9.2",
"v2.9.1",
"v2.9.0",
"v2.9.0rc2",
"v2.9.0rc1",
"v2.8.2",
"v2.8.1",
"v2.8.0",
"v2.8.0rc3",
"v2.8.0rc2",
"v2.8.0rc1",
"v2.7.1",
"v2.7.0",
"v2.7.0rc3",
"v2.7.0rc2",
"v2.7.0rc1",
"v2.6.1",
"v2.6.0",
"v2.6.0rc4",
"v2.6.0rc3",
"v2.6.0rc2",
"v2.6.0rc1",
"v2.5.0",
"v2.5.0rc2",
"v2.5.0rc1",
"v2.4.3",
"v2.4.3rc3",
"v2.4.3rc2",
"v2.4.3rc1",
"v2.4.2",
"v2.4.2rc3",
"v2.4.2rc2",
"v2.4.2rc1",
"v2.4.1",
"v2.4.1rc4",
"v2.4.1rc3",
"v2.4.1rc2",
"v2.4.1rc1",
"v2.4.0",
"v2.4.0rc5",
"v2.4.0rc4",
"v2.4.0rc3",
"v2.4.0rc2",
"v2.4.0rc1",
"v2.3.2",
"v2.3.2rc5",
"v2.3.2rc4",
"v2.3.2rc3",
"v2.3.2rc2",
"v2.3.2rc1",
"v2.3.1",
"v2.3.1rc3",
"v2.3.1rc2",
"v2.3.1rc1",
"v2.3.0",
"v2.3.0rc3",
"v2.3.0rc2",
"v2.3.0rc1",
"v2.2.0",
"v2.2.0rc2",
"v2.2.0rc1",
"v2.1.3",
"v2.1.2",
"v2.1.1",
"v2.1.0",
"v2.1.0rc6",
"v2.1.0rc5",
"v2.1.0rc4",
"v2.1.0rc3",
"v2.1.0rc2",
"v2.1.0rc1",
"v2.0.0",
"v2.0.0rc4",
"v2.0.0rc3",
"v2.0.0rc2",
"v2.0.0rc1",
"v1.6.1",
"v1.6.0",
"v1.6.0rc5",
"v1.6.0rc4",
"v1.6.0rc3",
"v1.6.0rc2",
"v1.6.0rc1",
"v1.5.1",
"v1.5.0",
"v1.5.0rc3",
"v1.5.0rc2",
"v1.5.0rc1",
"v1.4.7",
"v1.4.6",
"v1.4.5",
"v1.4.4",
"v1.4.3",
"v1.4.2",
"v1.4.1",
"v1.4rc6",
"v1.4rc5",
"v1.4rc4",
"v1.4rc3",
"v1.4rc2",
"v1.4rc1",
"v1.3.2",
"v1.3.1",
"v1.3",
"v1.2.2",
"v1.2.1",
"v1.2",
"v1.1.2",
"v1.1.1",
"v1.1",
"v1.0",
"v0.9.9",
"v0.9",
"v0.8",
"v0.7",
"v0.6",
"v0.1.2",
"v0.1.1",
"v0.1.0"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-36461.json"
}
}
],
"modified": "2026-10-28T02:30:53.358937990Z",
"provider": "osv",
"references": [
"https://github.com/mastodon/mastodon/releases/tag/v3.5.9",
"https://github.com/mastodon/mastodon/releases/tag/v4.0.5",
"https://github.com/mastodon/mastodon/releases/tag/v4.1.3",
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/36xxx/CVE-2023-36461.json",
"https://github.com/mastodon/mastodon/security/advisories/GHSA-9pxv-6qvf-pjwc",
"https://nvd.nist.gov/vuln/detail/CVE-2023-36461",
"https://github.com/mastodon/mastodon/commit/c5929798bf7e56cc2c79b15bed0c4692ded3dcb6"
],
"provider_metadata": {
"cwe_ids": [
"CWE-770"
],
"cna_assigner": "GitHub_M",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/36xxx/CVE-2023-36461.json"
}
},
"related_cves": [
{
"value": "CVE-2023-36461",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 522097,
"published_at": "2023-07-06T18:57:59.16+00:00"
}