{"id":"CVE-2026-21903","aliases":["EUVD-2026-2692","GHSA-h3c8-3472-7v7g"],"status":"published","title":"Junos OS: Subscribing to telemetry sensors at scale causes all FPCs to crash","description":"A Stack-based Buffer Overflow vulnerability in the Packet Forwarding Engine (pfe) of Juniper Networks Junos OS allows a network-based attacker, authenticated with low privileges to cause a Denial-of-Service (DoS).\n\n\n\nSubscribing to telemetry sensors at scale causes all FPC connections to drop, resulting in an FPC crash and restart.\nThe issue was not seen when YANG packages for the specific sensors were installed. \n\n\n\nThis issue affects Junos OS: \n\n\n\n  *  all versions before 22.4R3-S7,\n  *  23.2 version before 23.2R2-S4,\n  *  23.4 versions before 23.4R2.","severity":{"version":"4.0","score":7.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00399,"percentile":0.3449,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-121"],"published":"2026-01-15T20:18:36Z","modified":"2026-06-17T10:19:07Z","products":[{"vendor":"juniper","product":"junos"},{"vendor":"juniper networks","product":"junos os"}],"references":[{"url":"https://supportportal.juniper.net/JSA106022","tags":["vendor-advisory","Vendor Advisory"]},{"url":"https://kb.juniper.net/JSA106022","tags":["vendor-advisory","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-21903"},{"url":"https://github.com/advisories/GHSA-h3c8-3472-7v7g"}],"sources":{"cve":[{"id":"CVE-2026-21903","title":"Junos OS: Subscribing to telemetry sensors at scale causes all FPCs to crash","description":"A Stack-based Buffer Overflow vulnerability in the Packet Forwarding Engine (pfe) of Juniper Networks Junos OS allows a network-based attacker, authenticated with low privileges to cause a Denial-of-Service (DoS).\n\n\n\nSubscribing to telemetry sensors at scale causes all FPC connections to drop, resulting in an FPC crash and restart.\nThe issue was not seen when YANG packages for the specific sensors were installed. \n\n\n\nThis issue affects Junos OS: \n\n\n\n  *  all versions before 22.4R3-S7,\n  *  23.2 version before 23.2R2-S4,\n  *  23.4 versions before 23.4R2.","status":"published","published":"2026-01-15T20:18:36.767Z","modified":"2026-01-15T21:12:08.631Z","cvss":[{"version":"4.0","score":7.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L","level":"high","assessor":"cna"},{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"cna"}],"cwes":["CWE-121"],"updated_at":"2026-11-02T13:41:42.05254Z"}],"euvd":[{"id":"EUVD-2026-2692","description":"A Stack-based Buffer Overflow vulnerability in the Packet Forwarding Engine (pfe) of Juniper Networks Junos OS allows a network-based attacker, authenticated with low privileges to cause a Denial-of-Service (DoS).\n\n\n\nSubscribing to telemetry sensors at scale causes all FPC connections to drop, resulting in an FPC crash and restart.\nThe issue was not seen when YANG packages for the specific sensors were installed. \n\n\n\nThis issue affects Junos OS: \n\n\n\n  *  all versions before 22.4R3-S7,\n  *  23.2 version before 23.2R2-S4,\n  *  23.4 versions before 23.4R2.","status":"published","published":"2026-01-15T20:18:36Z","modified":"2026-01-15T21:12:08Z","cvss":[{"version":"4.0","score":7.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L","level":"high"}],"updated_at":"2026-11-02T19:48:51.36047Z"}],"ghsa":[{"id":"GHSA-h3c8-3472-7v7g","title":"A Stack-based Buffer Overflow vulnerability in the Packet Forwarding Engine (pfe) of Juniper...","description":"A Stack-based Buffer Overflow vulnerability in the Packet Forwarding Engine (pfe) of Juniper Networks Junos OS allows a network-based attacker, authenticated with low privileges to cause a Denial-of-Service (DoS).\n\n\n\nSubscribing to telemetry sensors at scale causes all FPC connections to drop, resulting in an FPC crash and restart.\nThe issue was not seen when YANG packages for the specific sensors were installed. \n\n\n\nThis issue affects Junos OS: \n\n\n\n  *  all versions before 22.4R3-S7,\n  *  23.2 version before 23.2R2-S4,\n  *  23.4 versions before 23.4R2.","status":"published","published":"2026-01-15T21:31:48Z","modified":"2026-01-15T21:31:54Z","cvss":[{"version":"4.0","score":7.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high"},{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-121"],"updated_at":"2026-11-02T15:05:38.149378Z"}],"nvd":[{"id":"CVE-2026-21903","description":"A Stack-based Buffer Overflow vulnerability in the Packet Forwarding Engine (pfe) of Juniper Networks Junos OS allows a network-based attacker, authenticated with low privileges to cause a Denial-of-Service (DoS).\n\n\n\nSubscribing to telemetry sensors at scale causes all FPC connections to drop, resulting in an FPC crash and restart.\nThe issue was not seen when YANG packages for the specific sensors were installed. \n\n\n\nThis issue affects Junos OS: \n\n\n\n  *  all versions before 22.4R3-S7,\n  *  23.2 version before 23.2R2-S4,\n  *  23.4 versions before 23.4R2.","status":"published","published":"2026-01-15T21:16:05.807Z","modified":"2026-06-17T10:19:07.297Z","cvss":[{"version":"4.0","score":7.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high","assessor":"secondary"},{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"secondary"}],"cwes":["CWE-121"],"updated_at":"2026-11-02T14:12:04.066712Z"}]}}