{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-21912", "assignerOrgId": "8cbe9d5a-a066-4c94-8978-4b15efeae968", "state": "PUBLISHED", "assignerShortName": "juniper", "dateReserved": "2026-01-05T17:32:48.710Z", "datePublished": "2026-01-15T20:24:20.087Z", "dateUpdated": "2026-01-15T20:50:28.949Z"}, "containers": {"cna": {"affected": [{"defaultStatus": "unaffected", "platforms": ["MX10k Series"], "product": "Junos OS", "vendor": "Juniper Networks", "versions": [{"lessThan": "21.2R3-S10", "status": "affected", "version": "0", "versionType": "semver"}, {"lessThan": "21.4R3-S9", "status": "affected", "version": "21.4", "versionType": "semver"}, {"lessThan": "22.2R3-S7", "status": "affected", "version": "22.2", "versionType": "semver"}, {"lessThan": "22.4R3-S6", "status": "affected", "version": "22.4", "versionType": "semver"}, {"lessThan": "23.2R2-S2", "status": "affected", "version": "23.2", "versionType": "semver"}, {"lessThan": "23.4R2-S3", "status": "affected", "version": "23.4", "versionType": "semver"}, {"lessThan": "24.2R2", "status": "affected", "version": "24.2", "versionType": "semver"}]}], "datePublic": "2026-01-14T17:00:00.000Z", "descriptions": [{"lang": "en", "supportingMedia": [{"base64": false, "type": "text/html", "value": "<span style=\"background-color: rgb(255, 255, 255);\">A Time-of-check Time-of-use (TOCTOU) Race Condition vulnerability in the method to collect FPC Ethernet firmware statistics&nbsp;of Juniper Networks Junos OS on MX10k Series allows a local, low-privileged attacker executing the 'show system firmware' CLI command to cause an LC480 or LC2101 line card to reset.<br></span><br>On MX10k Series systems with LC480 or LC2101 line cards, repeated execution of the 'show system firmware' CLI command can cause the line card to crash and restart. 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