{"id":"CVE-2023-36844","kind":"vulnerability","aliases":["CVE-2023-36844"],"related":[],"title":"juniper junos: A PHP External Variable Modification vulnerability in J-Web of Juniper Networks Junos OS on EX Series allows an…","description":"A PHP External Variable Modification vulnerability in J-Web of Juniper Networks Junos OS on EX Series allows an unauthenticated, network-based attacker to control certain, important environment variables.\n\nUsing a crafted request an attacker is able to modify \n\ncertain PHP environment variables leading to partial loss of integrity, which may allow chaining to other vulnerabilities.\nThis issue affects Juniper Networks Junos OS on EX Series:\n\n\n\n  *  All versions prior to 20.4R3-S9;\n  *  21.1 versions 21.1R1 and later;\n  *  21.2 versions prior to 21.2R3-S7;\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-S4;\n  *  22.2 versions \n\nprior to \n\n22.2R3-S2;\n  *  22.3 versions \n\nprior to 22.3R3-S1;\n  *  22.4 versions \n\nprior to \n\n22.4R2-S2, 22.4R3;\n  *  23.2 versions prior to \n\n23.2R1-S1, 23.2R2.","summary":"Juniper Junos OS on EX Series switches runs a PHP component that accepts crafted requests which overwrite certain PHP environment variables. An unauthenticated remote attacker can use this to partially compromise integrity and possibly chain it 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"},{"name":"juniper junos","fixed":[],"affected":"= 23.2","ecosystem":"vendor"}],"ecosystems":["vendor"],"tags":["ex-series","exploited","infrastructure","juniper","junos-os","network-gear"],"not_affected_if":["no-junos-os","non-ex-series-hardware"],"how_to_check":null,"fix":"Apply the mitigation or fixed Junos OS release from Juniper's advisory for CVE-2023-36844; CISA says to discontinue use of the 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":"2026-10-23T21:02:51+00:00","updated_at":"2026-10-23T22:29:04+00:00","category":"infrastructure","confidence":0.6,"triage":{"at":"2026-10-23T21:02:51Z","model":"claude-haiku-5-5","output":{"fix":"Apply the mitigation or fixed Junos OS release from Juniper's advisory for CVE-2023-36844; CISA says to discontinue use of the product if no mitigation is available.","reach":"network","impact":"medium","summary":"Juniper Junos OS on EX Series switches runs a PHP component that accepts crafted requests which overwrite certain PHP environment variables. An unauthenticated remote attacker can use this to partially compromise integrity and possibly chain it into further flaws.","category":"infrastructure","who_cares":["juniper","junos-os","ex-series","network-gear"],"confidence":0.6,"needs_auth":"no","worst_case":"Attacker alters PHP environment variables, partially compromising integrity and enabling chained attacks.","analyst_note":"Find the Juniper advisory for CVE-2023-36844 to get affected and fixed Junos versions and the specific mitigation commands; sources here give none.","how_to_check":"unknown","needs_analyst":true,"not_affected_if":["non-ex-series-hardware","no-junos-os"],"user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"high"},"cost_usd":0.000491,"input_tokens":2881,"output_tokens":406,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-2023':23A,26A '-36844':24A,27A '20.4':176C '21.1':180C,182C '21.2':186C,190C '21.3':194C,198C '21.4':202C,206C '22.1':210C,214C '22.2':218C,222C '22.3':226C,230C '22.4':234C,238C,242C '23.2':244C,248C,252C 'abl':142C 'accept':77B 'affect':164C 'allow':21A,122C,157C 'attack':89B,128C,140C 'base':127C 'certain':82B,131C,145C 'chain':99B,158C 'compon':75B 'compromis':95B 'control':130C 'craft':78B,137C 'cve':22A,25A 'environ':84B,133C,147C 'ex':19A,54B,69B,120C,170C 'ex-seri':53B 'exploit':56B 'extern':5A,106C 'flaw':103B 'gear':64B 'import':132C 'infrastructur':57B 'integr':96B,154C 'issu':163C 'j':11A,112C 'j-web':10A,111C 'junip':1A,14A,58B,65B,115C,165C 'juniper':28A,31A,33A,35A,37A,39A,41A,43A,45A,47A,49A,51A 'juno':2A,16A,60B,66B,117C,167C 'junos':29A,32A,34A,36A,38A,40A,42A,44A,46A,48A,50A,52A 'junos-o':59B 'later':185C 'lead':149C 'loss':152C 'may':156C 'modif':7A,108C 'modifi':144C 'network':15A,63B,116C,126C,166C 'network-bas':125C 'network-gear':62B 'os':17A,30A,61B,67B,118C,168C 'overwrit':81B 'partial':94B,151C 'php':4A,74B,83B,105C,146C 'possibl':98B 'prior':174C,188C,196C,204C,212C,220C,228C,236C,246C 'r1':183C,250C 'r1-s1':249C 'r2':240C,253C 'r2-s2':239C 'r3':178C,192C,200C,208C,216C,224C,232C,243C 'r3-s1':231C 'r3-s2':223C 'r3-s4':215C 'r3-s5':199C,207C 'r3-s7':191C 'r3-s9':177C 'remot':88B 'request':79B,138C 'run':72B 's1':233C,251C 's2':225C,241C 's4':217C 's5':201C,209C 's7':193C 's9':179C 'seri':20A,55B,70B,121C,171C 'switch':71B 'unauthent':87B,124C 'use':91B,135C 'variabl':6A,85B,107C,134C,148C 'version':173C,181C,187C,195C,203C,211C,219C,227C,235C,245C 'vulner':8A,109C,161C 'web':12A,113C","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-2023-36844","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2023-36844","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":"2026-10-25T12:39:23+00:00","note":null},{"source":"nvd","external_id":"CVE-2023-36844","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-36844","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"}