{"id":"CVE-2026-56331","aliases":["EUVD-2026-40440","GHSA-34p8-fh3m-376x","GHSA-994r-m5r3-f3p9"],"status":"published","title":"Capgo - Improper Error Handling in Accept Invitation Endpoint via Invalid Magic String","description":"Capgo before 12.128.2 contains improper error handling in the /private/accept_invitation endpoint that returns HTTP 500 instead of safe 4xx errors when magic_invite_string is invalid. Attackers can trigger this vulnerability using only the public key by submitting malformed magic_invite_string values to cause server errors and leak internal processing details.","severity":{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-08","score":0.00343,"percentile":0.28005,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-209"],"published":"2026-06-30T22:08:32Z","modified":"2026-10-28T02:30:36Z","products":[{"vendor":"cap-go","product":"capgo"},{"vendor":"capgo","product":"capgo"}],"references":[{"url":"https://github.com/Cap-go/capgo/security/advisories/GHSA-34p8-fh3m-376x","tags":["vendor-advisory","exploit","advisory"]},{"url":"https://www.vulncheck.com/advisories/capgo-improper-error-handling-in-accept-invitation-endpoint-via-invalid-magic-string","tags":["third-party-advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-56331","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-994r-m5r3-f3p9"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/56xxx/CVE-2026-56331.json","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-56331","title":"Capgo - Improper Error Handling in Accept Invitation Endpoint via Invalid Magic String","description":"Capgo before 12.128.2 contains improper error handling in the /private/accept_invitation endpoint that returns HTTP 500 instead of safe 4xx errors when magic_invite_string is invalid. Attackers can trigger this vulnerability using only the public key by submitting malformed magic_invite_string values to cause server errors and leak internal processing details.","status":"published","published":"2026-06-30T22:08:32.681Z","modified":"2026-07-01T14:42:21.453Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N","level":"medium","assessor":"cna"},{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-209"],"updated_at":"2026-11-02T13:36:51.6229Z"}],"euvd":[{"id":"EUVD-2026-40440","description":"Capgo before 12.128.2 contains improper error handling in the /private/accept_invitation endpoint that returns HTTP 500 instead of safe 4xx errors when magic_invite_string is invalid. Attackers can trigger this vulnerability using only the public key by submitting malformed magic_invite_string values to cause server errors and leak internal processing details.","status":"published","published":"2026-06-30T22:08:32Z","modified":"2026-07-01T14:42:21Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N","level":"medium"}],"updated_at":"2026-11-02T18:20:19.829772Z"}],"ghsa":[{"id":"GHSA-994r-m5r3-f3p9","title":"Capgo before 12.128.2 contains improper error handling in the /private/accept_invitation endpoint...","description":"Capgo before 12.128.2 contains improper error handling in the /private/accept_invitation endpoint that returns HTTP 500 instead of safe 4xx errors when magic_invite_string is invalid. Attackers can trigger this vulnerability using only the public key by submitting malformed magic_invite_string values to cause server errors and leak internal processing details.","status":"published","published":"2026-07-01T00:34:13Z","modified":"2026-07-01T00:34:25Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/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":"medium"},{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"cwes":["CWE-209"],"updated_at":"2026-11-02T15:09:07.106222Z"}],"nvd":[{"id":"CVE-2026-56331","description":"Capgo before 12.128.2 contains improper error handling in the /private/accept_invitation endpoint that returns HTTP 500 instead of safe 4xx errors when magic_invite_string is invalid. Attackers can trigger this vulnerability using only the public key by submitting malformed magic_invite_string values to cause server errors and leak internal processing details.","status":"published","published":"2026-06-30T23:17:30.493Z","modified":"2026-07-01T16:16:48.103Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/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":"medium","assessor":"secondary"},{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-209"],"updated_at":"2026-11-02T14:12:26.866638Z"}],"osv":[{"id":"CVE-2026-56331","title":"Capgo - Improper Error Handling in Accept Invitation Endpoint via Invalid Magic String","description":"Capgo before 12.128.2 contains improper error handling in the /private/accept_invitation endpoint that returns HTTP 500 instead of safe 4xx errors when magic_invite_string is invalid. Attackers can trigger this vulnerability using only the public key by submitting malformed magic_invite_string values to cause server errors and leak internal processing details.","status":"published","published":"2026-06-30T22:08:32.681Z","modified":"2026-10-28T02:30:36.622774879Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N","level":"medium"}],"cwes":["CWE-209"],"updated_at":"2026-11-02T15:45:11.609219Z"}]}}