{"id":"CVE-2021-0205","state":"PUBLISHED","title":"Junos OS: MX Series: Dynamic filter fails to match IPv6 prefix","description":"When the \"Intrusion Detection Service\" (IDS) feature is configured on Juniper Networks MX series with a dynamic firewall filter using IPv6 source or destination prefix, it may incorrectly match the prefix as /32, causing the filter to block unexpected traffic. This issue affects only IPv6 prefixes when used as source and destination. This issue affects MX Series devices using MS-MPC, MS-MIC or MS-SPC3 service cards with IDS service configured. This issue affects: Juniper Networks Junos OS 17.3 versions prior to 17.3R3-S10 on MX Series; 17.4 versions prior to 17.4R3-S3 on MX Series; 18.1 versions prior to 18.1R3-S11 on MX Series; 18.2 versions prior to 18.2R3-S6 on MX Series; 18.3 versions prior to 18.3R3-S4 on MX Series; 18.4 versions prior to 18.4R3-S6 on MX Series; 19.1 versions prior to 19.1R2-S2, 19.1R3-S3 on MX Series; 19.2 versions prior to 19.2R3-S1 on MX Series; 19.3 versions prior to 19.3R2-S5, 19.3R3-S1 on MX Series; 19.4 versions prior to 19.4R3 on MX Series; 20.1 versions prior to 20.1R2 on MX Series; 20.2 versions prior to 20.2R2 on MX Series;","publishedAt":"2021-01-15T17:35:53.539Z","updatedAt":"2024-09-16T17:28:25.455Z","severity":{"score":5.8,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L","source":"juniper"},"assigner":"juniper","products":["Juniper Networks Junos OS"],"affected":[{"vendor":"Juniper Networks","product":"Junos OS","versions":[{"version":"17.3","status":"affected","lessThan":"17.3R3-S10","versionType":"custom"},{"version":"17.4","status":"affected","lessThan":"17.4R3-S3","versionType":"custom"},{"version":"18.1","status":"affected","lessThan":"18.1R3-S11","versionType":"custom"},{"version":"18.2","status":"affected","lessThan":"18.2R3-S6","versionType":"custom"},{"version":"18.3","status":"affected","lessThan":"18.3R3-S4","versionType":"custom"},{"version":"18.4","status":"affected","lessThan":"18.4R3-S6","versionType":"custom"},{"version":"19.1","status":"affected","lessThan":"19.1R2-S2, 19.1R3-S3","versionType":"custom"},{"version":"19.2","status":"affected","lessThan":"19.2R3-S1","versionType":"custom"},{"version":"19.3","status":"affected","lessThan":"19.3R2-S5, 19.3R3-S1","versionType":"custom"},{"version":"19.4","status":"affected","lessThan":"19.4R3","versionType":"custom"},{"version":"20.1","status":"affected","lessThan":"20.1R2","versionType":"custom"},{"version":"20.2","status":"affected","lessThan":"20.2R2","versionType":"custom"}],"platforms":["MX Series"]}],"references":["https://kb.juniper.net/JSA11095"],"weaknesses":["CWE-284"],"ingestedAt":"2026-10-29T19:47:50.134Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2021/0xxx/CVE-2021-0205.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.1","cveMetadata":{"cveId":"CVE-2021-0205","state":"PUBLISHED","datePublished":"2021-01-15T17:35:53.539Z","dateUpdated":"2024-09-16T17:28:25.455Z","assignerShortName":"juniper","assignerOrgId":"8cbe9d5a-a066-4c94-8978-4b15efeae968","dateReserved":"2020-10-27T00:00:00.000Z"},"containers":{"cna":{"title":"Junos OS: MX Series: Dynamic filter fails to match IPv6 prefix","descriptions":[{"lang":"en","value":"When the \"Intrusion Detection Service\" (IDS) feature is configured on Juniper Networks MX series with a dynamic firewall filter using IPv6 source or destination prefix, it may incorrectly match the prefix as /32, causing the filter to block unexpected traffic. This issue affects only IPv6 prefixes when used as source and destination. This issue affects MX Series devices using MS-MPC, MS-MIC or MS-SPC3 service cards with IDS service configured. This issue affects: Juniper Networks Junos OS 17.3 versions prior to 17.3R3-S10 on MX Series; 17.4 versions prior to 17.4R3-S3 on MX Series; 18.1 versions prior to 18.1R3-S11 on MX Series; 18.2 versions prior to 18.2R3-S6 on MX Series; 18.3 versions prior to 18.3R3-S4 on MX Series; 18.4 versions prior to 18.4R3-S6 on MX Series; 19.1 versions prior to 19.1R2-S2, 19.1R3-S3 on MX Series; 19.2 versions prior to 19.2R3-S1 on MX Series; 19.3 versions prior to 19.3R2-S5, 19.3R3-S1 on MX Series; 19.4 versions prior to 19.4R3 on MX Series; 20.1 versions prior to 20.1R2 on MX Series; 20.2 versions prior to 20.2R2 on MX Series;"}],"affected":[{"vendor":"Juniper Networks","product":"Junos OS","versions":[{"version":"17.3","status":"affected","lessThan":"17.3R3-S10","versionType":"custom"},{"version":"17.4","status":"affected","lessThan":"17.4R3-S3","versionType":"custom"},{"version":"18.1","status":"affected","lessThan":"18.1R3-S11","versionType":"custom"},{"version":"18.2","status":"affected","lessThan":"18.2R3-S6","versionType":"custom"},{"version":"18.3","status":"affected","lessThan":"18.3R3-S4","versionType":"custom"},{"version":"18.4","status":"affected","lessThan":"18.4R3-S6","versionType":"custom"},{"version":"19.1","status":"affected","lessThan":"19.1R2-S2, 19.1R3-S3","versionType":"custom"},{"version":"19.2","status":"affected","lessThan":"19.2R3-S1","versionType":"custom"},{"version":"19.3","status":"affected","lessThan":"19.3R2-S5, 19.3R3-S1","versionType":"custom"},{"version":"19.4","status":"affected","lessThan":"19.4R3","versionType":"custom"},{"version":"20.1","status":"affected","lessThan":"20.1R2","versionType":"custom"},{"version":"20.2","status":"affected","lessThan":"20.2R2","versionType":"custom"}],"platforms":["MX Series"]}],"references":[{"url":"https://kb.juniper.net/JSA11095","tags":["x_refsource_CONFIRM"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"LOW","baseScore":5.8,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"CHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-284","description":"CWE-284 Improper Access Control","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"juniper","dateUpdated":"2021-01-15T17:35:53.000Z","orgId":"8cbe9d5a-a066-4c94-8978-4b15efeae968"},"configurations":[{"lang":"en","value":"The example of the configuration stanza affected by this issue is as follows:\n  [services ids]"}],"datePublic":"2021-01-13T00:00:00.000Z","exploits":[{"lang":"en","value":"Juniper SIRT is not aware of any malicious exploitation of this vulnerability."}],"solutions":[{"lang":"en","value":"The following software releases have been updated to resolve this specific issue: \n\nJunos OS: 17.3R3-S10, 17.4R3-S3, 18.1R3-S11, 18.2R3-S6, 18.3R3-S4, 18.4R3-S6, 19.1R2-S2, 19.1R3-S3, 19.2R3-S1, 19.3R2-S5, 19.3R3-S1, 19.4R3, 20.1R2, 20.2R2, 20.3R1 and all subsequent releases."}],"source":{"advisory":"JSA11095","defect":["1536100"],"discovery":"USER"},"workarounds":[{"lang":"en","value":"IDS configuration can be disabled."}],"x_generator":{"engine":"Vulnogram 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firewall filter using IPv6 source or destination prefix, it may incorrectly match the prefix as /32, causing the filter to block unexpected traffic. This issue affects only IPv6 prefixes when used as source and destination. This issue affects MX Series devices using MS-MPC, MS-MIC or MS-SPC3 service cards with IDS service configured. This issue affects: Juniper Networks Junos OS 17.3 versions prior to 17.3R3-S10 on MX Series; 17.4 versions prior to 17.4R3-S3 on MX Series; 18.1 versions prior to 18.1R3-S11 on MX Series; 18.2 versions prior to 18.2R3-S6 on MX Series; 18.3 versions prior to 18.3R3-S4 on MX Series; 18.4 versions prior to 18.4R3-S6 on MX Series; 19.1 versions prior to 19.1R2-S2, 19.1R3-S3 on MX Series; 19.2 versions prior to 19.2R3-S1 on MX Series; 19.3 versions prior to 19.3R2-S5, 19.3R3-S1 on MX Series; 19.4 versions prior to 19.4R3 on MX Series; 20.1 versions prior to 20.1R2 on MX Series; 20.2 versions prior to 20.2R2 on MX Series;"}]},"exploit":[{"lang":"en","value":"Juniper SIRT is not aware of any malicious exploitation of this vulnerability."}],"generator":{"engine":"Vulnogram 0.0.9"},"impact":{"cvss":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"LOW","baseScore":5.8,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"CHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L","version":"3.1"}},"problemtype":{"problemtype_data":[{"description":[{"lang":"eng","value":"CWE-284 Improper Access Control"}]}]},"references":{"reference_data":[{"name":"https://kb.juniper.net/JSA11095","refsource":"CONFIRM","url":"https://kb.juniper.net/JSA11095"}]},"solution":[{"lang":"en","value":"The following software releases have been updated to resolve this specific issue: \n\nJunos OS: 17.3R3-S10, 17.4R3-S3, 18.1R3-S11, 18.2R3-S6, 18.3R3-S4, 18.4R3-S6, 19.1R2-S2, 19.1R3-S3, 19.2R3-S1, 19.3R2-S5, 19.3R3-S1, 19.4R3, 20.1R2, 20.2R2, 20.3R1 and all subsequent releases."}],"source":{"advisory":"JSA11095","defect":["1536100"],"discovery":"USER"},"work_around":[{"lang":"en","value":"IDS configuration can be disabled."}]}},"adp":[{"title":"CVE Program Container","references":[{"url":"https://kb.juniper.net/JSA11095","tags":["x_refsource_CONFIRM","x_transferred"]}],"providerMetadata":{"shortName":"CVE","orgId":"af854a3a-2127-422b-91ae-364da2661108","dateUpdated":"2024-08-03T15:32:10.287Z"}}]}}}