{"id":"CVE-2023-36847","kind":"vulnerability","aliases":["CVE-2023-36847"],"related":[],"title":"juniper junos: A Missing Authentication for Critical Function vulnerability in Juniper Networks Junos OS on EX Series allows an…","description":"A Missing Authentication for Critical Function vulnerability in Juniper Networks Junos OS on EX Series allows an unauthenticated, network-based attacker to cause limited impact to the file system integrity.\n\n\n\n\n\nWith a specific request to installAppPackage.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 EX 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-S4;\n  *  22.1 versions \n\nprior to \n\n22.1R3-S3;\n  *  22.2 versions \n\nprior to \n\n22.2R3-S1;\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 EX Series switches lets an unauthenticated network attacker send a request to installAppPackage.php in J-Web and upload arbitrary files. The attacker can alter part of the file system, which may be chained into further compromise.","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":["ex-series","exploited","infrastructure","j-web","junos-os","network-appliance"],"not_affected_if":["j-web-disabled","patched-junos-version"],"how_to_check":"Check whether J-Web is enabled on EX Series switches and whether the device runs an affected Junos OS version (unknown which versions the sources list).","fix":"Apply the vendor mitigation or fixed Junos OS release per Juniper's advisory; if none is available, stop using the product as CISA directs. Restricting access to J-Web management is a likely interim step but the sources do not confirm it.","status":"open","published_at":"2023-08-17T20:15:10+00:00","first_seen_at":"2026-10-23T19:11:51+00:00","triaged_at":"2026-10-23T21:02:55+00:00","updated_at":"2026-10-23T22:29:04+00:00","category":"infrastructure","confidence":0.6,"triage":{"at":"2026-10-23T21:02:55Z","model":"claude-haiku-5-5","output":{"fix":"Apply the vendor mitigation or fixed Junos OS release per Juniper's advisory; if none is available, stop using the product as CISA directs. Restricting access to J-Web management is a likely interim step but the sources do not confirm it.\nunknown","reach":"network","impact":"medium","summary":"Juniper Junos OS on EX Series switches lets an unauthenticated network attacker send a request to installAppPackage.php in J-Web and upload arbitrary files. The attacker can alter part of the file system, which may be chained into further compromise.","category":"infrastructure","who_cares":["junos-os","ex-series","j-web","network-appliance"],"confidence":0.6,"needs_auth":"no","worst_case":"Attacker uploads arbitrary files, altering part of the file system and enabling chained attacks.","analyst_note":"Find the affected and fixed Junos OS versions and the exact mitigation in Juniper's advisory for CVE-2023-36847 (via the Juniper security advisories site), since the sources left them blank.","how_to_check":"Check whether J-Web is enabled on EX Series switches and whether the device runs an affected Junos OS version (unknown which versions the sources list).\nunknown","needs_analyst":true,"not_affected_if":["j-web-disabled","patched-junos-version"],"user_interaction":"no","needs_special_setup":"yes","severity_if_unknown":"high"},"cost_usd":0.000534,"input_tokens":2916,"output_tokens":485,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-2023':20A,23A '-36847':21A,24A '20.4':192C '21.1':196C,198C '21.2':202C,206C '21.3':210C,214C '21.4':218C,222C '22.1':226C,230C '22.2':234C,238C '22.3':242C,246C,250C '22.4':252C,256C,260C 'abl':148C 'affect':180C 'allow':18A,118C,173C 'alter':90B 'applianc':61B 'arbitrari':85B,151C 'attack':73B,88B,124C,146C 'authent':5A,105C,144C 'base':123C 'caus':126C 'certain':165C 'chain':99B,174C 'compromis':102B 'critic':7A,107C 'cve':19A,22A 'doesn':141C 'ex':16A,49B,66B,116C,186C 'ex-seri':48B 'exploit':51B 'file':86B,94B,131C,152C,169C 'function':8A,108C 'impact':128C 'infrastructur':52B 'installapppackage.php':78B,139C 'integr':133C,162C 'issu':179C 'j':54B,81B,155C 'j-web':53B,80B,154C 'junip':1A,11A,62B,111C,181C 'juniper':25A,28A,30A,32A,34A,36A,38A,40A,42A,44A,46A 'juno':2A,13A,57B,63B,113C,183C 'junos':26A,29A,31A,33A,35A,37A,39A,41A,43A,45A,47A 'junos-o':56B 'later':201C 'lead':157C 'let':69B 'limit':127C 'loss':160C 'may':97B,172C 'miss':4A,104C 'network':12A,60B,72B,112C,122C,182C 'network-appli':59B 'network-bas':121C 'os':14A,27A,58B,64B,114C,184C 'part':91B,166C 'prior':190C,204C,212C,220C,228C,236C,244C,254C 'r1':199C 'r2':248C,258C 'r2-s1':257C 'r2-s2':247C 'r3':194C,208C,216C,224C,232C,240C,251C,261C 'r3-s1':239C 'r3-s3':231C 'r3-s4':223C 'r3-s5':215C 'r3-s6':207C 'r3-s8':193C 'request':76B,137C 'requir':143C 's1':241C,259C 's2':249C 's3':233C 's4':225C 's5':217C 's6':209C 's8':195C 'send':74B 'seri':17A,50B,67B,117C,187C 'specif':136C 'switch':68B 'system':95B,132C,170C 'unauthent':71B,120C 'upload':84B,150C 'version':189C,197C,203C,211C,219C,227C,235C,243C,253C 'via':153C 'vulner':9A,109C,177C 'web':55B,82B,156C","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-2023-36847","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2023-36847","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":"2026-10-25T15:39:41+00:00","note":null},{"source":"nvd","external_id":"CVE-2023-36847","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-36847","severity":null,"published_at":"2023-08-17T20:15:10+00:00","modified_at":"2026-06-17T06:07:13+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"}