{"id":"CVE-2026-126932","kind":"vulnerability","aliases":["CVE-2026-126932"],"related":[],"title":"Zipline: authenticated users bypass disabled MIME types via file metadata","description":"Zipline 4.6.2 before 4.8.0 contains a policy bypass vulnerability that allows authenticated users to evade administrator-disabled MIME types by editing file metadata. Attackers can upload a permitted file, then set a disabled type such as text/html through PATCH /api/user/files/:id so /raw/:id serves that Content-Type.","summary":"Zipline 4.6.2 before 4.8.0 lets a logged-in user change a file's Content-Type through the file metadata API, even when the administrator has disabled that type. The attacker uploads a permitted file, then sets a disabled type such as text/html so the raw file endpoint serves it under that type.","severity":"medium","cvss":5.3,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["package","self-hosted","zipline"],"not_affected_if":["no-user-uploads","version-4.8.0-or-later"],"how_to_check":"- Check the installed Zipline version; affected versions are 4.6.2 up to but not including `4.8.0`.\n- Review whether administrators have disabled any MIME types in Zipline settings, since the bypass only matters when a disabled type is in use.","fix":"- Zipline: upgrade to `4.8.0` or later.","status":"open","published_at":"2026-11-11T23:17:22+00:00","first_seen_at":"2026-11-11T23:29:41+00:00","triaged_at":"2026-11-11T23:31:23+00:00","updated_at":"2026-11-11T23:31:23+00:00","category":"package","confidence":0.7,"triage":{"at":"2026-11-11T23:31:23Z","model":"claude-haiku-5-5","output":{"fix":"- Zipline: upgrade to `4.8.0` or later.","reach":"network","title":"Zipline: authenticated users bypass disabled MIME types via file metadata","impact":"medium","summary":"Zipline 4.6.2 before 4.8.0 lets a logged-in user change a file's Content-Type through the file metadata API, even when the administrator has disabled that type. The attacker uploads a permitted file, then sets a disabled type such as text/html so the raw file endpoint serves it under that type.","audience":"businesses","category":"package","nicknames":[],"who_cares":["zipline","self-hosted"],"confidence":0.7,"fix_status":"available","needs_auth":"yes","worst_case":"Authenticated user serves HTML from the file host, enabling stored XSS.","analyst_note":"Ecosystem and product fields are empty because no product is listed; the affected product is Zipline.","how_to_check":"- Check the installed Zipline version; affected versions are 4.6.2 up to but not including `4.8.0`.\n- Review whether administrators have disabled any MIME types in Zipline settings, since the bypass only matters when a disabled type is in use.","plain_action":"","product_name":"","needs_analyst":false,"not_affected_if":["version-4.8.0-or-later","no-user-uploads"],"who_is_affected":"Teams that self-host Zipline 4.6.2 or later before 4.8.0 and let users upload files. Exposure depends on administrators having disabled MIME types for security reasons; a deployment with a permissive MIME policy gains little from the bypass. Instances on 4.8.0 or later, or with no user accounts, can skip it.","user_interaction":"no","product_ecosystem":"","needs_special_setup":"no","severity_if_unknown":"medium"},"cost_usd":0.000764,"input_tokens":4643,"output_tokens":600,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-126932':13A,16A '-2026':12A,15A '/api/user/files':116C '/raw':119C '4.6.2':23B,77C '4.8.0':25B,79C 'administr':47B,92C 'administrator-dis':91C 'allow':86C 'api':43B 'attack':53B,100C 'authent':2A,87C 'bypass':4A,83C 'chang':32B 'contain':80C 'content':37B,124C 'content-typ':36B,123C 'cve':11A,14A 'disabl':5A,49B,61B,93C,109C 'edit':97C 'endpoint':70B 'evad':90C 'even':44B 'file':9A,34B,41B,57B,69B,98C,105C 'host':20B 'id':117C,120C 'let':26B 'log':29B 'logged-in':28B 'metadata':10A,42B,99C 'mime':6A,94C 'packag':17B 'patch':115C 'permit':56B,104C 'polici':82C 'raw':68B 'self':19B 'self-host':18B 'serv':71B,121C 'set':59B,107C 'text/html':65B,113C 'type':7A,38B,51B,62B,75B,95C,110C,125C 'upload':54B,102C 'user':3A,31B,88C 'via':8A 'vulner':84C 'ziplin':1A,21B,22B,76C","nicknames":[],"mitigations":[],"who_affected":"Teams that self-host Zipline 4.6.2 or later before 4.8.0 and let users upload files. Exposure depends on administrators having disabled MIME types for security reasons; a deployment with a permissive MIME policy gains little from the bypass. Instances on 4.8.0 or later, or with no user accounts, can skip it.","tier":"C","verified":{},"analyst_revisit_at":null,"fix_status":"available","audience":"businesses","plain_action":null,"pkeys":[],"ptokens":[],"labels":["medium","package","selfhosted","zipline"],"campaign_type":null,"search_a":"'-126932':13A,16A '-2026':12A,15A 'authent':2A 'bypass':4A 'cve':11A,14A 'disabl':5A 'file':9A 'metadata':10A 'mime':6A 'type':7A 'user':3A 'via':8A 'ziplin':1A","search_b":"'4.6.2':23B '4.8.0':25B 'administr':47B 'api':43B 'attack':53B 'chang':32B 'content':37B 'content-typ':36B 'disabl':49B,61B 'endpoint':70B 'even':44B 'file':34B,41B,57B,69B 'host':20B 'let':26B 'log':29B 'logged-in':28B 'metadata':42B 'packag':17B 'permit':56B 'raw':68B 'self':19B 'self-host':18B 'serv':71B 'set':59B 'text/html':65B 'type':38B,51B,62B,75B 'upload':54B 'user':31B 'ziplin':21B,22B","search_c":"'/api/user/files':116C '/raw':119C '4.6.2':77C '4.8.0':79C 'administr':92C 'administrator-dis':91C 'allow':86C 'attack':100C 'authent':87C 'bypass':83C 'contain':80C 'content':124C 'content-typ':123C 'disabl':93C,109C 'edit':97C 'evad':90C 'file':98C,105C 'id':117C,120C 'metadata':99C 'mime':94C 'patch':115C 'permit':104C 'polici':82C 'serv':121C 'set':107C 'text/html':113C 'type':95C,110C,125C 'upload':102C 'user':88C 'vulner':84C 'ziplin':76C","cause_entry":null,"cause_path":null,"disclosures_checked_at":null,"first_public_at":"2026-09-27T23:13:13+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/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","cvss_by":"disclosure@vulncheck.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-126932","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-126932","severity":null,"published_at":"2026-11-11T23:17:22+00:00","modified_at":"2026-11-11T23:17:22+00:00","first_seen_at":"2026-11-11T23:29:41+00:00","fetched_at":"2026-11-11T23:29:41+00:00","note":null}],"documents":[{"id":129945,"url":"https://github.com/diced/zipline/commit/fc8e886ca841b86a3f677cd7dac1bf9a5bd45b2c","title":"Patch: github.com","kind":"other","source":"nvd","publisher":"vendor","text":null,"published_at":null,"relation":"fix","confidence":null,"note":"Patch: github.com"},{"id":129946,"url":"https://github.com/diced/zipline/releases/tag/v4.8.0","title":"Release notes: github.com","kind":"release","source":"nvd","publisher":"vendor","text":null,"published_at":null,"relation":"fix","confidence":null,"note":"Release notes: github.com"},{"id":129947,"url":"https://github.com/diced/zipline/security/advisories/GHSA-rgxm-54cf-whf7","title":"Vendor advisory: github.com","kind":"vendor","source":"nvd","publisher":"vendor","text":null,"published_at":"2026-09-27T23:13:13+00:00","relation":"advisory","confidence":null,"note":"Vendor advisory: github.com"},{"id":129948,"url":"https://www.vulncheck.com/advisories/zipline-4.6.2-before-4.8.0-disabled-mime-type-policy-bypass-via-file-metadata-update","title":"Third-party advisory: www.vulncheck.com","kind":"advisory","source":"nvd","publisher":"research","text":null,"published_at":null,"relation":"advisory","confidence":null,"note":"Third-party advisory: www.vulncheck.com"}],"disclosures":[],"exploit_sources":[],"notice":"Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai"}