{"id":35908,"date":"2026-01-15T15:01:46","date_gmt":"2026-01-15T15:01:46","guid":{"rendered":"http:\/\/localhost\/?p=35908"},"modified":"2026-01-15T15:01:46","modified_gmt":"2026-01-15T15:01:46","slug":"junos-os-subscribing-to-telemetry-sensors-at-scale-causes-all-fpcs-to-crash","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=35908","title":{"rendered":"Junos OS: Subscribing to telemetry sensors at scale causes all FPCs to crash_CVE-2026-21903"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;A Stack-based Buffer Overflow vulnerability in the Packet Forwarding Engine (pfe) of Juniper Networks Junos OS allows a network-based attacker,\u00a0authenticated\u00a0with 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:\u00a0\\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.&#8221;,&#8221;published&#8221;:&#8221;2026-01-15T20:18:36.767Z&#8221;,&#8221;modified&#8221;:&#8221;2026-01-15T20:18:36.767Z&#8221;,&#8221;type&#8221;:&#8221;cve&#8221;,&#8221;title&#8221;:&#8221;Junos OS: Subscribing to telemetry sensors at scale causes all FPCs to crash&#8221;,&#8221;source&#8221;:&#8221;juniper&#8221;,&#8221;references&#8221;:&#8221;https:\/\/supportportal.juniper.net\/JSA106022\\nhttps:\/\/kb.juniper.net\/JSA106022&#8243;,&#8221;id&#8221;:&#8221;CVE-2026-21903&#8243;,&#8221;bulletinFamily&#8221;:&#8221;&#8221;,&#8221;cwe&#8221;:[&#8220;CWE-121&#8243;],&#8221;cvelist&#8221;:null,&#8221;sourceData&#8221;:&#8221;Juniper Networks Junos OS 0\\nJuniper Networks Junos OS 23.2\\nJuniper Networks Junos OS 23.4&#8243;,&#8221;sourceHref&#8221;:&#8221;&#8221;,&#8221;cvss&#8221;:{&#8220;score&#8221;:6.5,&#8221;severity&#8221;:&#8221;MEDIUM&#8221;,&#8221;vector&#8221;:&#8221;CVSS:3.1\/AV:N\/AC:L\/PR:L\/UI:N\/S:U\/C:N\/I:N\/A:H&#8221;,&#8221;version&#8221;:&#8221;3.1&#8243;},&#8221;cvss2&#8243;:{},&#8221;cvss3&#8243;:{&#8220;version&#8221;:&#8221;&#8221;,&#8221;vectorString&#8221;:&#8221;&#8221;,&#8221;baseScore&#8221;:0,&#8221;baseSeverity&#8221;:&#8221;&#8221;,&#8221;attackVector&#8221;:&#8221;&#8221;,&#8221;attackComplexity&#8221;:&#8221;&#8221;,&#8221;privilegesRequired&#8221;:&#8221;&#8221;,&#8221;userInteraction&#8221;:&#8221;&#8221;,&#8221;scope&#8221;:&#8221;&#8221;,&#8221;confidentialityImpact&#8221;:&#8221;&#8221;,&#8221;integrityImpact&#8221;:&#8221;&#8221;,&#8221;availabilityImpact&#8221;:&#8221;&#8221;,&#8221;cvssV3&#8243;:{&#8220;version&#8221;:&#8221;&#8221;,&#8221;vectorString&#8221;:&#8221;&#8221;,&#8221;baseScore&#8221;:0,&#8221;baseSeverity&#8221;:&#8221;&#8221;,&#8221;attackVector&#8221;:&#8221;&#8221;,&#8221;attackComplexity&#8221;:&#8221;&#8221;,&#8221;privilegesRequired&#8221;:&#8221;&#8221;,&#8221;userInteraction&#8221;:&#8221;&#8221;,&#8221;scope&#8221;:&#8221;&#8221;,&#8221;confidentialityImpact&#8221;:&#8221;&#8221;,&#8221;integrityImpact&#8221;:&#8221;&#8221;,&#8221;availabilityImpact&#8221;:&#8221;&#8221;}},&#8221;href&#8221;:&#8221;&#8221;,&#8221;category_name&#8221;:&#8221;CVE&#8221;,&#8221;post_link&#8221;:&#8221;&#8221;,&#8221;product&#8221;:&#8221;Junos OS&#8221;,&#8221;version&#8221;:&#8221;0&#8243;,&#8221;vendor&#8221;:&#8221;Juniper Networks&#8221;,&#8221;ai_description&#8221;:&#8221;&#8221;,&#8221;ai_severity&#8221;:&#8221;&#8221;,&#8221;ai_vendor&#8221;:&#8221;&#8221;,&#8221;ai_product&#8221;:&#8221;&#8221;,&#8221;ai_version&#8221;:&#8221;&#8221;,&#8221;ai_score&#8221;:0}<\/p>\n","protected":false},"excerpt":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;A Stack-based Buffer Overflow vulnerability in the Packet Forwarding Engine (pfe) of Juniper Networks Junos OS allows a network-based attacker,\u00a0authenticated\u00a0with low privileges to cause a&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[6,8,26,12,21,13,7,11,5],"class_list":["post-35908","post","type-post","status-publish","format-standard","hentry","category-category_cve","tag-cve","tag-cvss","tag-cvss-65","tag-exploit","tag-medium","tag-news","tag-security","tag-tapic","tag-vulnerability"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.5 - 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