{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2021-31378", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2021-31378", "idYear": 2021, "status": "PUBLISHED", "publishedAt": "2021-10-19T18:17:18.243Z", "updatedAt": "2024-09-16T20:36:31.752Z", "importedAt": "2026-10-24T01:56:32.228Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "Junos OS: An attacker sending spoofed RADIUS messages to a Junos OS device configured for broadband services may cause broadband subscribers to remain stuck in a \"Terminating\" state.", "summary": "In broadband environments, including but not limited to Enhanced Subscriber Management, (CHAP, PPP, DHCP, etc.), on Juniper Networks Junos OS devices where RADIUS servers are configured for managing subscriber access and a subscriber is logged in and then requests to logout, the subscriber may be forced into a \"Terminating\" state by an attacker who is able to send spoofed messages appearing to originate from trusted RADIUS server(s) destined to the device in response to the subscriber's request. These spoofed messages cause the Junos OS General Authentication Service (authd) daemon to force the broadband subscriber into this \"Terminating\" state which the subscriber will not recover from thereby causing a Denial of Service (DoS) to the endpoint device. Once in the \"Terminating\" state, the endpoint subscriber will no longer be able to access the network. Restarting the authd daemon on the Junos OS device will temporarily clear the subscribers out of the \"Terminating\" state. As long as the attacker continues to send these spoofed packets and subscribers request to be logged out, the subscribers will be returned to the \"Terminating\" state thereby creating a persistent Denial of Service to the subscriber. An indicator of compromise may be seen by displaying the output of \"show subscribers summary\". The presence of subscribers in the \"Terminating\" state may indicate the issue is occurring. This issue affects: Juniper Networks Junos OS 17.3 versions prior to 17.3R3-S12; 17.4 versions prior to 17.4R3-S5; 18.1 versions prior to 18.1R3-S13; 18.2 versions prior to 18.2R3-S8; 18.3 versions prior to 18.3R3-S5; 18.4 versions prior to 18.4R2-S8, 18.4R3-S9; 19.1 versions prior to 19.1R3-S6; 19.2 versions prior to 19.2R1-S7, 19.2R3-S3; 19.3 versions prior to 19.3R2-S6, 19.3R3-S3; 19.4 versions prior to 19.4R1-S4, 19.4R1-S4, 19.4R3-S3; 20.1 versions prior to 20.1R3; 20.2 versions prior to 20.2R3-S1; 20.3 versions prior to 20.3R3; 20.4 versions prior to 20.4R3; 21.1 versions prior to 21.1R2. This issue does not affect: Juniper Networks Junos OS 12.3 version 12.3R1 and later versions; 15.1 version 15.1R1 and later versions.", "affected": [ { "vendor": "Juniper Networks", "product": "Junos OS", "versions": [ { "version": "17.3", "status": "affected", "versionType": "custom", "lessThan": "17.3R3-S12" }, { "version": "17.4", "status": "affected", "versionType": "custom", "lessThan": "17.4R3-S5" }, { "version": "18.1", "status": "affected", "versionType": "custom", "lessThan": "18.1R3-S13" }, { "version": "18.2", "status": "affected", "versionType": "custom", "lessThan": "18.2R3-S8" }, { "version": "18.3", "status": "affected", "versionType": "custom", "lessThan": "18.3R3-S5" }, { "version": "18.4", "status": "affected", "versionType": "custom", "lessThan": "18.4R2-S8, 18.4R3-S9" }, { "version": "19.1", "status": "affected", "versionType": "custom", "lessThan": "19.1R3-S6" }, { "version": "19.2", "status": "affected", "versionType": "custom", "lessThan": "19.2R1-S7, 19.2R3-S3" }, { "version": "19.3", "status": "affected", "versionType": "custom", "lessThan": "19.3R2-S6, 19.3R3-S3" }, { "version": "19.4", "status": "affected", "versionType": "custom", "lessThan": "19.4R1-S4, 19.4R1-S4, 19.4R3-S3" }, { "version": "20.1", "status": "affected", "versionType": "custom", "lessThan": "20.1R3" }, { "version": "20.2", "status": "affected", "versionType": "custom", "lessThan": "20.2R3-S1" }, { "version": "20.3", "status": "affected", "versionType": "custom", "lessThan": "20.3R3" }, { "version": "20.4", "status": "affected", "versionType": "custom", "lessThan": "20.4R3" }, { "version": "21.1", "status": "affected", "versionType": "custom", "lessThan": "21.1R2" }, { "version": "12.3R1", "status": "unaffected", "versionType": "custom", "lessThan": "12.3*" }, { "version": "15.1R1", "status": "unaffected", "versionType": "custom", "lessThan": "15.1*" } ] } ] } } }