{"cve":{"cve_id":"CVE-2021-27771","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":0.00669,"epss_percentile":0.47104,"epss_as_of":"2026-06-23","description":"User SID can be modified resulting in an Arbitrary File Upload or deletion of directories causing a Denial of Service. When interacting in a normal matter with the Sametime chat application, users hold a cookie containing their session ID (SID). This value is also used when sending chat messages, receiving notifications and/or transferring files.","published_at":"2022-05-12T21:25:27.080000Z","last_modified_at":null,"cvss_v3_score":8.2,"cvss_v3_vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:H","cvss_v3_severity":"HIGH","cvss_v4_score":null,"cvss_v4_vector":null,"cvss_v4_severity":null,"ssvc_decision":null,"ssvc_exploitation":null,"ssvc_automatable":null,"ssvc_technical_impact":null,"cwes":["CWE-434","CWE-22"],"nvd_references":["https://support.hcltechsw.com/csm?id=kb_article&sysparm_article=KB0097430"],"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":"2026-06-28T23:15:22.552059Z"},"effective_severity":"HIGH","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":"L","value_label":"Low"},{"metric":"UI","name":"User Interaction","value":"R","value_label":"Required"},{"metric":"S","name":"Scope","value":"C","value_label":"Changed"},{"metric":"C","name":"Confidentiality","value":"L","value_label":"Low"},{"metric":"I","name":"Integrity","value":"L","value_label":"Low"},{"metric":"A","name":"Availability","value":"H","value_label":"High"}]},"cvss_v4_decoded":{"version":null,"metrics":[]},"affected":[{"vendor_slug":"hcl-software","vendor_name":"HCL Software","product_slug":"sametime","product_name":"Sametime","version_start":"11.6","version_start_inclusive":true,"version_end":"11.6","version_end_inclusive":true,"cpe23_uri":"cve5:hcl-software:sametime:11.6:11.6"}],"exploit_refs":[],"news":[],"references":[{"url":"https://support.hcltechsw.com/csm?id=kb_article&sysparm_article=KB0097430","source_type":"MISC","tags":[]}],"timeline":[{"type":"published","at":"2022-05-12T21:25:27.080000Z","label":"CVE published","source":null},{"type":"cvss_changed","at":"2026-06-28T17:17:49.905977Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:17:49.905977Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:17:49.905977Z","label":"CVSS score revised","source":"cvelistv5"}]}