{"cve":{"cve_id":"CVE-2026-49991","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":null,"epss_percentile":null,"epss_as_of":null,"description":"RustFS is a distributed object storage system built in Rust. In 1.0.0-beta.4, authenticated users with only PutObject permission on their own bucket can exploit a path traversal vulnerability in the Snowball auto-extract feature to write arbitrary objects into other users' buckets, completely breaking multi-tenant isolation. The vulnerability chains three flaws: No ../ sanitization in tar entry key normalization; IAM wildcard matching uses raw (uncleaned) paths; and Filesystem path cleaning resolves ../ across bucket boundaries.","published_at":"2026-06-26T20:01:29.896000Z","last_modified_at":null,"cvss_v3_score":8.6,"cvss_v3_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N","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-22","CWE-862"],"nvd_references":["https://github.com/rustfs/rustfs/security/advisories/GHSA-f4vq-9ffr-m8m3"],"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":"2026-06-28T17:55:10.688071Z","updated_at":"2026-06-28T23:30:46.591291Z"},"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":"N","value_label":"None"},{"metric":"UI","name":"User Interaction","value":"N","value_label":"None"},{"metric":"S","name":"Scope","value":"C","value_label":"Changed"},{"metric":"C","name":"Confidentiality","value":"N","value_label":"None"},{"metric":"I","name":"Integrity","value":"H","value_label":"High"},{"metric":"A","name":"Availability","value":"N","value_label":"None"}]},"cvss_v4_decoded":{"version":null,"metrics":[]},"affected":[{"vendor_slug":"rustfs","vendor_name":"rustfs","product_slug":"rustfs","product_name":"rustfs","version_start":"1.0.0-beta.4","version_start_inclusive":true,"version_end":"1.0.0-beta.4","version_end_inclusive":true,"cpe23_uri":"cve5:rustfs:rustfs:1.0.0-beta.4:1.0.0-beta.4"}],"exploit_refs":[],"news":[],"references":[{"url":"https://github.com/rustfs/rustfs/security/advisories/GHSA-f4vq-9ffr-m8m3","source_type":"VENDOR_ADVISORY","tags":["advisory"]}],"timeline":[{"type":"published","at":"2026-06-26T20:01:29.896000Z","label":"CVE published","source":null}]}