{"id":"CVE-2026-104817","aliases":["EUVD-2026-99239","GHSA-4x7v-qx8f-g3p8"],"status":"published","title":"Misskey: Lack of rate limiting and size restrictions in RSS fetching API","description":"Misskey is an open source, federated social media platform. From 12.112.1 until 2026.7.0, the unauthenticated fetch-rss API lacks rate limiting and response-size restrictions and performs synchronous XML parsing. An attacker can trigger unbounded outbound HTTP requests and synchronous parsing, exhausting instance resources, amplifying requests toward third-party servers, or probing network-reachable services even when federation is disabled. This issue is fixed in version 2026.7.0.","severity":{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:L/SI:N/SA:L","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.0046,"percentile":0.40303,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-405","CWE-770","CWE-918"],"published":"2026-10-13T18:39:30Z","modified":"2026-10-28T02:30:30Z","products":[{"vendor":"misskey-dev","product":"misskey"}],"references":[{"url":"https://github.com/misskey-dev/misskey/security/advisories/GHSA-4x7v-qx8f-g3p8","tags":["x_refsource_CONFIRM","advisory"]},{"url":"https://github.com/misskey-dev/misskey/commit/a12ee2e5d72c40252e11a164b2231667c9697667","tags":["x_refsource_MISC","fix"]},{"url":"https://github.com/misskey-dev/misskey/releases/tag/2026.7.0","tags":["x_refsource_MISC","web"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/104xxx/CVE-2026-104817.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-104817","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-104817","title":"Misskey: Lack of rate limiting and size restrictions in RSS fetching API","description":"Misskey is an open source, federated social media platform. From 12.112.1 until 2026.7.0, the unauthenticated fetch-rss API lacks rate limiting and response-size restrictions and performs synchronous XML parsing. An attacker can trigger unbounded outbound HTTP requests and synchronous parsing, exhausting instance resources, amplifying requests toward third-party servers, or probing network-reachable services even when federation is disabled. This issue is fixed in version 2026.7.0.","status":"published","published":"2026-10-13T18:39:30.169Z","modified":"2026-10-13T19:04:03.012Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:L/SI:N/SA:L","level":"high","assessor":"cna"}],"cwes":["CWE-405","CWE-770","CWE-918"],"updated_at":"2026-11-02T14:20:09.098623Z"}],"euvd":[{"id":"EUVD-2026-99239","description":"Misskey is an open source, federated social media platform. From 12.112.1 until 2026.7.0, the unauthenticated fetch-rss API lacks rate limiting and response-size restrictions and performs synchronous XML parsing. An attacker can trigger unbounded outbound HTTP requests and synchronous parsing, exhausting instance resources, amplifying requests toward third-party servers, or probing network-reachable services even when federation is disabled. This issue is fixed in version 2026.7.0.","status":"published","published":"2026-10-13T18:39:30Z","modified":"2026-10-13T19:04:03Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:L/SI:N/SA:L","level":"high"}],"updated_at":"2026-11-02T17:27:18.769576Z"}],"nvd":[{"id":"CVE-2026-104817","description":"Misskey is an open source, federated social media platform. From 12.112.1 until 2026.7.0, the unauthenticated fetch-rss API lacks rate limiting and response-size restrictions and performs synchronous XML parsing. An attacker can trigger unbounded outbound HTTP requests and synchronous parsing, exhausting instance resources, amplifying requests toward third-party servers, or probing network-reachable services even when federation is disabled. This issue is fixed in version 2026.7.0.","status":"published","published":"2026-10-13T19:17:55.697Z","modified":"2026-10-16T20:04:29.76Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:L/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high","assessor":"secondary"}],"cwes":["CWE-405","CWE-770","CWE-918"],"updated_at":"2026-11-02T14:12:57.132005Z"}],"osv":[{"id":"CVE-2026-104817","title":"Misskey: Lack of rate limiting and size restrictions in RSS fetching API","description":"Misskey is an open source, federated social media platform. From 12.112.1 until 2026.7.0, the unauthenticated fetch-rss API lacks rate limiting and response-size restrictions and performs synchronous XML parsing. An attacker can trigger unbounded outbound HTTP requests and synchronous parsing, exhausting instance resources, amplifying requests toward third-party servers, or probing network-reachable services even when federation is disabled. This issue is fixed in version 2026.7.0.","status":"published","published":"2026-10-13T18:39:30.169Z","modified":"2026-10-28T02:30:30.654110552Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:L/SI:N/SA:L","level":"high"}],"cwes":["CWE-405","CWE-770","CWE-918"],"updated_at":"2026-11-02T15:44:54.236592Z"}]}}