{"id":"CVE-2023-36847","published":"2023-08-17T20:15:10Z","modified":"2026-06-17T06:07:13Z","title":"Juniper Junos OS EX Series Missing Authentication for Critical Function Vulnerability","vendor":"Juniper","product":"Junos OS","tier":"core","eol":null,"description":{"text":"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.","provenance":"source","from":"NVD"},"summary":{"text":"A Missing Authentication for Critical Function flaw in Juniper Networks Junos OS on EX Series switches lets the J-Web interface accept requests to installAppPackage.php without any login. An unauthenticated attacker with network access to the device can use that request to upload arbitrary files to a portion of the file system, compromising its integrity and potentially enabling chaining to other vulnerabilities.","provenance":"ai","model":"claude-haiku-5-5","generatedAt":"2026-10-29T13:44:02Z"},"cvss":{"score":5.3,"severity":"MEDIUM","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","provenance":"source","from":"NVD"},"epss":{"score":0.83455,"percentile":0.99682,"date":"2026-10-29","provenance":"source"},"kev":{"dateAdded":"2023-11-13","dueDate":"2023-11-17","ransomware":false,"requiredAction":"Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.","notes":"https://supportportal.juniper.net/s/article/2023-08-Out-of-Cycle-Security-Bulletin-Junos-OS-SRX-Series-and-EX-Series-Multiple-vulnerabilities-in-J-Web-can-be-combined-to-allow-a-preAuth-Remote-Code-Execution?language=en_US;  https://nvd.nist.gov/vuln/detail/CVE-2023-36847","provenance":"source"},"vulncheckKev":{"dateAdded":"2023-08-29","exploitedFirstSeen":"2023-08-29","ransomware":true,"evidence":[{"url":"https://twitter.com/Shadowserver/status/1696512418036486246","date":"2023-08-29"},{"url":"https://supportportal.juniper.net/s/article/2023-08-Out-of-Cycle-Security-Bulletin-Junos-OS-SRX-Series-and-EX-Series-Multiple-vulnerabilities-in-J-Web-can-be-combined-to-allow-a-preAuth-Remote-Code-Execution","date":"2023-11-08"},{"url":"https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json","date":"2023-11-13"},{"url":"https://www.cisa.gov/sites/default/files/2024-11/aa24-317a-2023-top-routinely-exploited-vulnerabilities.pdf","date":"2024-11-12"},{"url":"https://www.cyber.gov.au/about-us/view-all-content/alerts-and-advisories/2023-top-routinely-exploited-vulnerabilities","date":"2024-11-13"},{"url":"https://blog.qualys.com/vulnerabilities-threat-research/2025/02/25/defense-lessons-from-the-black-basta-ransomware-playbook","date":"2025-02-25"},{"url":"https://www.tenable.com/blog/verizon-2025-dbir-tenable-research-collaboration","date":"2025-04-23"},{"url":"https://www.verizon.com/business/resources/T32e/reports/2025-dbir-data-breach-investigations-report.pdf","date":"2025-04-25"}],"evidenceTotal":8,"provenance":"source"},"exploited":true,"otx":{"pulseCount":50,"pulses":[{"name":"Actively_Exploited_Kev | Oct 29, 2026","url":"https://otx.alienvault.com/pulse/6ae20c1db17e7057ae7d9ad1","created":"2026-10-28"},{"name":"Actively_Exploited_Kev | Oct 28, 2026","url":"https://otx.alienvault.com/pulse/6ae0ba7e0e2a97ff7b218819","created":"2026-10-27"},{"name":"Actively_Exploited_Kev | Oct 27, 2026","url":"https://otx.alienvault.com/pulse/6adf68b85c3e852f3c111d18","created":"2026-10-26"},{"name":"Actively_Exploited_Kev | Oct 24, 2026","url":"https://otx.alienvault.com/pulse/6adb740e397c3ad4799aa4cd","created":"2026-10-23"},{"name":"Actively_Exploited_Kev | Oct 23, 2026","url":"https://otx.alienvault.com/pulse/6ada236fcfba2dfa730ea482","created":"2026-10-22"},{"name":"Actively_Exploited_Kev | Oct 22, 2026","url":"https://otx.alienvault.com/pulse/6ad8d33a077cbb5cab524d80","created":"2026-10-21"},{"name":"Actively_Exploited_Kev | Oct 21, 2026","url":"https://otx.alienvault.com/pulse/6ad78130c4d1ac2be83a8b6d","created":"2026-10-20"},{"name":"Actively_Exploited_Kev | Oct 20, 2026","url":"https://otx.alienvault.com/pulse/6ad62f63c24a405a3423cc13","created":"2026-10-19"},{"name":"Actively_Exploited_Kev | Oct 19, 2026","url":"https://otx.alienvault.com/pulse/6ad4dda174e5797d0bd238b7","created":"2026-10-18"},{"name":"Actively_Exploited_Kev | Oct 18, 2026","url":"https://otx.alienvault.com/pulse/6ad38c22e1848f8189d1c121","created":"2026-10-17"}],"provenance":"machine"},"cwes":[{"id":"CWE-306","name":"Missing Authentication for Critical Functionality"}],"references":[{"url":"https://supportportal.juniper.net/JSA72300","tags":["Vendor Advisory"]},{"url":"https://supportportal.juniper.net/JSA72300","tags":["Vendor Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-36847","tags":["US Government Resource"]}],"techniques":[{"id":"T1190","name":"Exploit Public-Facing Application","tactics":["initial-access"],"provenance":"source","basis":"ctid-kev","bases":["ctid-kev"],"basisDetail":"CTID Mappings Explorer KEV 07/28/2025 (ATT&CK 16.1); capability: Missing Authentication","mappingType":"exploitation_technique","evidence":[],"comment":"This vulnerability is exploited through a Missing Authentication for Critical Function weakness in Juniper Networks Junos OS on EX Series devices. Attackers leverage this vulnerability to impact file system integrity by sending a crafted request to the `installAppPackage.php` endpoint, which does not require authentication. This manipulation allows the upload of arbitrary files via J-Web, leading to a loss of integrity for a certain part of the file system and enabling attackers to chain this vulnerability with others, potentially leading to further exploitation.","confidence":"high"},{"id":"T1059","name":"Command and Scripting Interpreter","tactics":["execution"],"provenance":"source","basis":"ctid-kev","bases":["ctid-kev"],"basisDetail":"CTID Mappings Explorer KEV 07/28/2025 (ATT&CK 16.1); capability: Missing Authentication","mappingType":"primary_impact","evidence":[],"comment":"This vulnerability is exploited through a Missing Authentication for Critical Function weakness in Juniper Networks Junos OS on EX Series devices. Attackers leverage this vulnerability to impact file system integrity by sending a crafted request to the `installAppPackage.php` endpoint, which does not require authentication. This manipulation allows the upload of arbitrary files via J-Web, leading to a loss of integrity for a certain part of the file system and enabling attackers to chain this vulnerability with others, potentially leading to further exploitation.","confidence":"high"}],"reports":[],"affected":[],"advisories":[],"euvd":{"id":"EUVD-2023-40767","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2023-40767","exploited":true,"exploitedSince":"2023-11-13","provenance":"source"},"exploits":[],"exploitSources":null,"exploitRefs":[],"flow":[{"stage":"exploitation","techniques":["T1190"],"provenance":"source"},{"stage":"primary","techniques":["T1059"],"provenance":"source"}],"timeline":[{"date":"2023-08-17","kind":"published","label":"Published (NVD)","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-36847","provenance":"source"},{"date":"2023-08-29","kind":"exploited-reported","label":"Exploitation first reported (VulnCheck KEV evidence)","url":"https://twitter.com/Shadowserver/status/1696512418036486246","provenance":"source"},{"date":"2023-11-13","kind":"kev","label":"Added to CISA KEV","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","provenance":"source"},{"date":"2023-11-13","kind":"euvd-exploited","label":"ENISA EUVD: exploited","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2023-40767","provenance":"source"}],"speed":{"daysToPublicExploit":null,"firstExploitFrom":null,"daysToKev":88},"priority":{"score":71.6,"factors":[{"name":"In a KEV catalog","points":35.0,"detail":"listed in CISA KEV and VulnCheck KEV"},{"name":"Recent KEV listing","points":0.0,"detail":"added 1157 days ago"},{"name":"Known ransomware use","points":10.0,"detail":"CISA KEV and VulnCheck KEV: Known"},{"name":"EPSS percentile","points":19.94,"detail":"percentile 0.9968"},{"name":"Named in threat reports","points":0.0,"detail":"0 reports"},{"name":"Public exploit code","points":0.0,"detail":"none found"},{"name":"Mentioned in OTX pulses","points":3.0,"detail":"50 pulses"},{"name":"CVSS severity","points":3.71,"detail":"base score 5.3"},{"name":"End-of-life product","points":0.0,"detail":"supported or unknown"}]}}