{"id":"CVE-2023-36846","kind":"vulnerability","aliases":["CVE-2023-36846"],"related":[],"title":"juniper junos: A Missing Authentication for Critical Function vulnerability in Juniper Networks Junos OS on SRX Series allows an…","description":"A Missing Authentication for Critical Function vulnerability in Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause limited impact to the file system integrity.\n\n\n\nWith a specific request to user.php that doesn't require authentication an attacker is able to upload arbitrary files via J-Web, leading to a loss of \n\nintegrity\n\nfor a certain \n\npart of the file system, which may allow chaining to other vulnerabilities.\n\n\nThis issue affects Juniper Networks Junos OS on SRX Series:\n\n\n\n  *  All versions prior to 20.4R3-S8;\n  *  21.1 versions 21.1R1 and later;\n  *  21.2 versions prior to 21.2R3-S6;\n  *  21.3 versions \n\nprior to \n\n 21.3R3-S5;\n  *  21.4 versions \n\nprior to \n\n21.4R3-S5;\n  *  22.1 versions \n\nprior to \n\n22.1R3-S3;\n  *  22.2 versions \n\nprior to \n\n22.2R3-S2;\n  *  22.3 versions \n\nprior to \n\n22.3R2-S2, 22.3R3;\n  *  22.4 versions \n\nprior to \n\n22.4R2-S1, 22.4R3.","summary":"Juniper Junos OS on SRX firewalls has a J-Web flaw where a request to user.php skips authentication and lets an attacker upload arbitrary files. The sources say this is exploited in the wild and can chain into further flaws.","severity":"high","cvss":5.3,"epss":null,"exploited":true,"exploited_at":"2023-11-13T00:00:00+00:00","products":[{"name":"Juniper Junos OS","fixed":[],"affected":"","ecosystem":"vendor"},{"name":"juniper junos","fixed":["20.4"],"affected":"< 20.4","ecosystem":"vendor"},{"name":"juniper junos","fixed":[],"affected":"= 20.4","ecosystem":"vendor"},{"name":"juniper junos","fixed":[],"affected":"= 21.1","ecosystem":"vendor"},{"name":"juniper junos","fixed":[],"affected":"= 21.2","ecosystem":"vendor"},{"name":"juniper junos","fixed":[],"affected":"= 21.3","ecosystem":"vendor"},{"name":"juniper junos","fixed":[],"affected":"= 21.4","ecosystem":"vendor"},{"name":"juniper junos","fixed":[],"affected":"= 22.1","ecosystem":"vendor"},{"name":"juniper junos","fixed":[],"affected":"= 22.2","ecosystem":"vendor"},{"name":"juniper junos","fixed":[],"affected":"= 22.3","ecosystem":"vendor"},{"name":"juniper junos","fixed":[],"affected":"= 22.4","ecosystem":"vendor"}],"ecosystems":["vendor"],"tags":["exploited","infrastructure","j-web","juniper","junos","srx"],"not_affected_if":["j-web-disabled","non-srx-platform"],"how_to_check":null,"fix":"Apply the Juniper mitigation for CVE-2023-36846 per vendor instructions, or stop using the affected product if no mitigation is available.","status":"open","published_at":"2023-08-17T20:15:10+00:00","first_seen_at":"2026-10-23T19:11:51+00:00","triaged_at":"2026-10-23T21:02:52+00:00","updated_at":"2026-10-23T22:29:04+00:00","category":"infrastructure","confidence":0.7,"triage":{"at":"2026-10-23T21:02:52Z","model":"claude-haiku-5-5","output":{"fix":"Apply the Juniper mitigation for CVE-2023-36846 per vendor instructions, or stop using the affected product if no mitigation is available.","reach":"network","impact":"medium","summary":"Juniper Junos OS on SRX firewalls has a J-Web flaw where a request to user.php skips authentication and lets an attacker upload arbitrary files. The sources say this is exploited in the wild and can chain into further flaws.","category":"infrastructure","who_cares":["juniper","junos","srx","j-web"],"confidence":0.7,"needs_auth":"no","worst_case":"unauthenticated attacker uploads arbitrary files to the firewall file system","analyst_note":"Find the Juniper security advisory for CVE-2023-36846 to get affected Junos versions, fixed releases and the exact mitigation steps, including whether disabling J-Web closes the exposure.","how_to_check":"unknown","needs_analyst":true,"not_affected_if":["j-web-disabled","non-srx-platform"],"user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"high"},"cost_usd":0.000485,"input_tokens":2913,"output_tokens":387,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-2023':20A,23A '-36846':21A,24A '20.4':186C '21.1':190C,192C '21.2':196C,200C '21.3':204C,208C '21.4':212C,216C '22.1':220C,224C '22.2':228C,232C '22.3':236C,240C,244C '22.4':246C,250C,254C 'abl':142C 'affect':174C 'allow':18A,112C,167C 'arbitrari':80B,145C 'attack':78B,118C,140C 'authent':5A,74B,99C,138C 'base':117C 'caus':120C 'certain':159C 'chain':93B,168C 'critic':7A,101C 'cve':19A,22A 'doesn':135C 'exploit':48B,87B 'file':81B,125C,146C,163C 'firewal':61B 'flaw':67B,96B 'function':8A,102C 'impact':122C 'infrastructur':49B 'integr':127C,156C 'issu':173C 'j':51B,65B,149C 'j-web':50B,64B,148C 'junip':1A,11A,53B,56B,105C,175C 'juniper':25A,28A,30A,32A,34A,36A,38A,40A,42A,44A,46A 'juno':2A,13A,54B,57B,107C,177C 'junos':26A,29A,31A,33A,35A,37A,39A,41A,43A,45A,47A 'later':195C 'lead':151C 'let':76B 'limit':121C 'loss':154C 'may':166C 'miss':4A,98C 'network':12A,106C,116C,176C 'network-bas':115C 'os':14A,27A,58B,108C,178C 'part':160C 'prior':184C,198C,206C,214C,222C,230C,238C,248C 'r1':193C 'r2':242C,252C 'r2-s1':251C 'r2-s2':241C 'r3':188C,202C,210C,218C,226C,234C,245C,255C 'r3-s2':233C 'r3-s3':225C 'r3-s5':209C,217C 'r3-s6':201C 'r3-s8':187C 'request':70B,131C 'requir':137C 's1':253C 's2':235C,243C 's3':227C 's5':211C,219C 's6':203C 's8':189C 'say':84B 'seri':17A,111C,181C 'skip':73B 'sourc':83B 'specif':130C 'srx':16A,55B,60B,110C,180C 'system':126C,164C 'unauthent':114C 'upload':79B,144C 'user.php':72B,133C 'version':183C,191C,197C,205C,213C,221C,229C,237C,247C 'via':147C 'vulner':9A,103C,171C 'web':52B,66B,150C 'wild':90B","nicknames":[],"mitigations":[],"who_affected":null,"tier":null,"verified":{},"analyst_revisit_at":null,"first_public_at":"2023-08-17T20:15:10+00:00","kev":{"dateAdded":"2023-11-13","dueDate":"2023-11-17","requiredAction":"Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.","knownRansomwareCampaignUse":"Unknown"},"cvss_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","cvss_by":"sirt@juniper.net","poc_count":0,"sources":[{"source":"kev","external_id":"CVE-2023-36846","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2023-36846","severity":null,"published_at":"2023-11-13T00:00:00+00:00","modified_at":null,"first_seen_at":"2026-10-23T19:11:51+00:00","fetched_at":"2026-10-25T17:39:56+00:00","note":null},{"source":"nvd","external_id":"CVE-2023-36846","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-36846","severity":null,"published_at":"2023-08-17T20:15:10+00:00","modified_at":"2026-06-17T06:07:12+00:00","first_seen_at":"2026-10-23T22:29:04+00:00","fetched_at":"2026-10-23T22:29:04+00:00","note":null}],"documents":[],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}