{"id":"CVE-2026-46713","aliases":["EUVD-2026-52485","GHSA-w8x2-gpq6-jxvf"],"status":"published","title":"Misskey: JSON-LD signature validation + compaction may lead to improper activity handling","description":"Misskey is an open source, federated social media platform. Versions 12.37.0 and later, but prior to 2026.5.4, contain a vulnerability in the JSON-LD signature validation and compaction process that allows spoofed activities to be accepted as valid. This issue has been fixed in version 2026.5.4.","severity":{"version":"4.0","score":9.2,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:H/SA:N","level":"critical","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.0028,"percentile":0.20696,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-347"],"published":"2026-08-03T21:37:45Z","modified":"2026-10-28T02:31:06Z","products":[{"vendor":"misskey-dev","product":"misskey"}],"references":[{"url":"https://github.com/misskey-dev/misskey/security/advisories/GHSA-w8x2-gpq6-jxvf","tags":["x_refsource_CONFIRM","advisory"]},{"url":"https://github.com/misskey-dev/misskey/releases/tag/2026.5.4","tags":["x_refsource_MISC","web"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46713.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-46713","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-46713","title":"Misskey: JSON-LD signature validation + compaction may lead to improper activity handling","description":"Misskey is an open source, federated social media platform. Versions 12.37.0 and later, but prior to 2026.5.4, contain a vulnerability in the JSON-LD signature validation and compaction process that allows spoofed activities to be accepted as valid. This issue has been fixed in version 2026.5.4.","status":"published","published":"2026-08-03T21:37:45.657Z","modified":"2026-08-04T15:44:53.013Z","cvss":[{"version":"4.0","score":9.2,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:H/SA:N","level":"critical","assessor":"cna"}],"cwes":["CWE-347"],"updated_at":"2026-11-02T13:47:06.353366Z"}],"euvd":[{"id":"EUVD-2026-52485","description":"Misskey is an open source, federated social media platform. Versions 12.37.0 and later, but prior to 2026.5.4, contain a vulnerability in the JSON-LD signature validation and compaction process that allows spoofed activities to be accepted as valid. This issue has been fixed in version 2026.5.4.","status":"published","published":"2026-08-03T21:37:45Z","modified":"2026-08-04T15:44:53Z","cvss":[{"version":"4.0","score":9.2,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:H/SA:N","level":"critical"}],"updated_at":"2026-11-02T18:02:22.965583Z"}],"nvd":[{"id":"CVE-2026-46713","description":"Misskey is an open source, federated social media platform. Versions 12.37.0 and later, but prior to 2026.5.4, contain a vulnerability in the JSON-LD signature validation and compaction process that allows spoofed activities to be accepted as valid. This issue has been fixed in version 2026.5.4.","status":"published","published":"2026-08-03T22:16:49.017Z","modified":"2026-10-23T21:10:00.157Z","cvss":[{"version":"4.0","score":9.2,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:H/SA:N/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":"critical","assessor":"secondary"}],"cwes":["CWE-347"],"updated_at":"2026-11-02T14:12:34.643497Z"}],"osv":[{"id":"CVE-2026-46713","title":"Misskey: JSON-LD signature validation + compaction may lead to improper activity handling","description":"Misskey is an open source, federated social media platform. Versions 12.37.0 and later, but prior to 2026.5.4, contain a vulnerability in the JSON-LD signature validation and compaction process that allows spoofed activities to be accepted as valid. This issue has been fixed in version 2026.5.4.","status":"published","published":"2026-08-03T21:37:45.657Z","modified":"2026-10-28T02:31:06.21381939Z","cvss":[{"version":"4.0","score":9.2,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:H/SA:N","level":"critical"}],"cwes":["CWE-347"],"updated_at":"2026-11-02T15:45:06.231145Z"}]}}