{"cve":{"cve_id":"CVE-2026-33173","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":0.0039,"epss_percentile":0.31933,"epss_as_of":"2026-08-26","description":"Active Storage allows users to attach cloud and local files in Rails applications. Prior to versions 8.1.2.1, 8.0.4.1, and 7.2.3.1, `DirectUploadsController` accepts arbitrary metadata from the client and persists it on the blob. Because internal flags like `identified` and `analyzed` are stored in the same metadata hash, a direct-upload client can set these flags to skip MIME detection and analysis. This allows an attacker to upload arbitrary content while claiming a safe `content_type`, bypassing any validations that rely on Active Storage's automatic content type identification. Versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 contain a patch.","published_at":"2026-03-23T23:21:29.843000Z","last_modified_at":null,"cvss_v3_score":null,"cvss_v3_vector":null,"cvss_v3_severity":null,"cvss_v4_score":5.3,"cvss_v4_vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N","cvss_v4_severity":"MEDIUM","ssvc_decision":null,"ssvc_exploitation":"none","ssvc_automatable":false,"ssvc_technical_impact":"partial","cwes":["CWE-925"],"nvd_references":["https://github.com/rails/rails/security/advisories/GHSA-qcfx-2mfw-w4cg","https://github.com/rails/rails/commit/707c0f1f41f067fdf96d54e99d43b28dfaae7e53","https://github.com/rails/rails/commit/8fcb934caadc79c8cc4ce53287046d0f67005b3e","https://github.com/rails/rails/commit/d9502f5214e2198245a4c1defe9cd02a7c8057d0","https://github.com/rails/rails/releases/tag/v7.2.3.1","https://github.com/rails/rails/releases/tag/v8.0.4.1","https://github.com/rails/rails/releases/tag/v8.1.2.1"],"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":"2026-06-29T23:46:59.033383Z"},"effective_severity":"MEDIUM","badges":[],"impact_analysis":[],"cvss_v3_decoded":{"version":null,"metrics":[]},"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":"P","value_label":"Passive"},{"metric":"VC","name":"Confidentiality (Vulnerable System)","value":"N","value_label":"None"},{"metric":"VI","name":"Integrity (Vulnerable System)","value":"L","value_label":"Low"},{"metric":"VA","name":"Availability (Vulnerable System)","value":"N","value_label":"None"},{"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":"rails","vendor_name":"rails","product_slug":"activestorage","product_name":"activestorage","version_start":">= 8.1.0.beta1, < 8.1.2.1","version_start_inclusive":true,"version_end":">= 8.1.0.beta1, < 8.1.2.1","version_end_inclusive":true,"cpe23_uri":"cve5:rails:activestorage:>= 8.1.0.beta1, < 8.1.2.1:>= 8.1.0.beta1, < 8.1.2.1"},{"vendor_slug":"rails","vendor_name":"rails","product_slug":"activestorage","product_name":"activestorage","version_start":">= 8.0.0.beta1, < 8.0.4.1","version_start_inclusive":true,"version_end":">= 8.0.0.beta1, < 8.0.4.1","version_end_inclusive":true,"cpe23_uri":"cve5:rails:activestorage:>= 8.0.0.beta1, < 8.0.4.1:>= 8.0.0.beta1, < 8.0.4.1"},{"vendor_slug":"rails","vendor_name":"rails","product_slug":"activestorage","product_name":"activestorage","version_start":"< 7.2.3.1","version_start_inclusive":true,"version_end":"< 7.2.3.1","version_end_inclusive":true,"cpe23_uri":"cve5:rails:activestorage:< 7.2.3.1:< 7.2.3.1"}],"exploit_refs":[],"news":[],"references":[{"url":"https://github.com/rails/rails/security/advisories/GHSA-qcfx-2mfw-w4cg","source_type":"VENDOR_ADVISORY","tags":["advisory"]},{"url":"https://github.com/rails/rails/commit/707c0f1f41f067fdf96d54e99d43b28dfaae7e53","source_type":"PATCH","tags":["patch"]},{"url":"https://github.com/rails/rails/commit/8fcb934caadc79c8cc4ce53287046d0f67005b3e","source_type":"PATCH","tags":["patch"]},{"url":"https://github.com/rails/rails/commit/d9502f5214e2198245a4c1defe9cd02a7c8057d0","source_type":"PATCH","tags":["patch"]},{"url":"https://github.com/rails/rails/releases/tag/v7.2.3.1","source_type":"PATCH","tags":["patch"]},{"url":"https://github.com/rails/rails/releases/tag/v8.0.4.1","source_type":"PATCH","tags":["patch"]},{"url":"https://github.com/rails/rails/releases/tag/v8.1.2.1","source_type":"PATCH","tags":["patch"]}],"timeline":[{"type":"published","at":"2026-03-23T23:21:29.843000Z","label":"CVE published","source":null},{"type":"cvss_changed","at":"2026-06-28T17:53:15.351162Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:53:15.351162Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:53:15.351162Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"ssvc_changed","at":"2026-06-29T23:46:59.033383Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-06-29T23:46:59.033383Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-06-29T23:46:59.033383Z","label":"SSVC decision revised","source":"vulnrichment"}]}