{"cve":{"cve_id":"CVE-2026-49955","is_kev":false,"kev_date_added":null,"kev_vendor_project":null,"kev_product":null,"kev_vulnerability_name":null,"kev_short_description":null,"kev_required_action":null,"kev_due_date":null,"kev_known_ransomware":null,"kev_notes":null,"kev_cwes":null,"epss_score":0.00586,"epss_percentile":0.43432,"epss_as_of":"2026-06-23","description":"Hermes WebUI before version 0.51.270 contains a resource exhaustion vulnerability that allows unauthenticated remote attackers to degrade service availability by repeatedly calling the passkey options endpoint without completing assertion. Attackers can send unlimited POST requests to the authentication endpoint, causing unbounded growth of the challenge store file and excessive CPU and disk I/O through repeated JSON file rewrites.","published_at":"2026-06-09T16:05:33.140000Z","last_modified_at":null,"cvss_v3_score":5.3,"cvss_v3_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","cvss_v3_severity":"MEDIUM","cvss_v4_score":6.9,"cvss_v4_vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","cvss_v4_severity":"MEDIUM","ssvc_decision":null,"ssvc_exploitation":null,"ssvc_automatable":null,"ssvc_technical_impact":null,"cwes":["CWE-770"],"nvd_references":["https://github.com/nesquena/hermes-webui/releases/tag/v0.51.270","https://github.com/nesquena/hermes-webui/pull/3624","https://github.com/nesquena/hermes-webui/pull/3674","https://github.com/nesquena/hermes-webui/commit/58528a4d88b0fa4f7b822e31d6051c669769bd3b","https://www.vulncheck.com/advisories/hermes-webui-resource-exhaustion-via-passkey-options"],"vuln_status":null,"trending_score":null,"is_trending":false,"has_trended":false,"trended_number_one":false,"trending_peak_score":null,"trending_peak_rank":null,"started_trending_at":null,"trended_number_one_at":null,"summary_generated":null,"summary_generated_at":null,"summary_model":null,"created_at":"2026-06-24T00:09:39.878444Z","updated_at":"2026-06-28T23:30:46.591291Z"},"effective_severity":"MEDIUM","badges":[],"impact_analysis":[],"cvss_v3_decoded":{"version":"3.1","metrics":[{"metric":"AV","name":"Attack Vector","value":"N","value_label":"Network"},{"metric":"AC","name":"Attack Complexity","value":"L","value_label":"Low"},{"metric":"PR","name":"Privileges Required","value":"N","value_label":"None"},{"metric":"UI","name":"User Interaction","value":"N","value_label":"None"},{"metric":"S","name":"Scope","value":"U","value_label":"Unchanged"},{"metric":"C","name":"Confidentiality","value":"N","value_label":"None"},{"metric":"I","name":"Integrity","value":"N","value_label":"None"},{"metric":"A","name":"Availability","value":"L","value_label":"Low"}]},"cvss_v4_decoded":{"version":"4.0","metrics":[{"metric":"AV","name":"Attack Vector","value":"N","value_label":"Network"},{"metric":"AC","name":"Attack Complexity","value":"L","value_label":"Low"},{"metric":"AT","name":"Attack Requirements","value":"N","value_label":"None"},{"metric":"PR","name":"Privileges Required","value":"N","value_label":"None"},{"metric":"UI","name":"User Interaction","value":"N","value_label":"None"},{"metric":"VC","name":"Confidentiality (Vulnerable System)","value":"N","value_label":"None"},{"metric":"VI","name":"Integrity (Vulnerable System)","value":"N","value_label":"None"},{"metric":"VA","name":"Availability (Vulnerable System)","value":"L","value_label":"Low"},{"metric":"SC","name":"Confidentiality (Subsequent System)","value":"N","value_label":"None"},{"metric":"SI","name":"Integrity (Subsequent System)","value":"N","value_label":"None"},{"metric":"SA","name":"Availability (Subsequent System)","value":"N","value_label":"None"}]},"affected":[{"vendor_slug":"nesquena","vendor_name":"nesquena","product_slug":"hermes-webui","product_name":"hermes-webui","version_start":"0","version_start_inclusive":true,"version_end":"0.51.270","version_end_inclusive":false,"cpe23_uri":"cve5:nesquena:hermes-webui:0:0.51.270"}],"exploit_refs":[],"news":[],"references":[{"url":"https://github.com/nesquena/hermes-webui/releases/tag/v0.51.270","source_type":"PATCH","tags":["patch"]},{"url":"https://github.com/nesquena/hermes-webui/pull/3624","source_type":"PATCH","tags":["patch"]},{"url":"https://github.com/nesquena/hermes-webui/pull/3674","source_type":"PATCH","tags":["patch"]},{"url":"https://github.com/nesquena/hermes-webui/commit/58528a4d88b0fa4f7b822e31d6051c669769bd3b","source_type":"PATCH","tags":["patch"]},{"url":"https://www.vulncheck.com/advisories/hermes-webui-resource-exhaustion-via-passkey-options","source_type":"VENDOR_ADVISORY","tags":["advisory"]}],"timeline":[{"type":"published","at":"2026-06-09T16:05:33.140000Z","label":"CVE published","source":null},{"type":"cvss_changed","at":"2026-06-28T17:55:10.688071Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:55:10.688071Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:55:10.688071Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:55:10.688071Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:55:10.688071Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:55:10.688071Z","label":"CVSS score revised","source":"cvelistv5"}]}