{"id":"CVE-2026-21917","state":"PUBLISHED","title":"Junos OS: SRX Series: Specifically malformed SSL packet causes FPC crash","description":"An Improper Validation of Syntactic Correctness of Input vulnerability in the Web-Filtering module of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS).\n\nIf an SRX device configured for UTM Web-Filtering receives a specifically malformed SSL packet, this will cause an FPC crash and restart.\nThis issue affects Junos OS on SRX Series:\n\n\n\n  *  23.2 versions from 23.2R2-S2 before 23.2R2-S5, \n  *  23.4 versions from 23.4R2-S1 before 23.4R2-S5,\n  *  24.2 versions before 24.2R2-S2,\n  *  24.4 versions before 24.4R1-S3, 24.4R2.\n\n\nEarlier versions of Junos are also affected, but no fix is available.","publishedAt":"2026-01-15T20:27:11.214Z","updatedAt":"2026-01-15T21:12:37.455Z","severity":{"score":8.7,"label":"High","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/AU:Y/R:A/RE:M","source":"juniper"},"assigner":"juniper","products":["Juniper Networks Junos OS"],"affected":[{"vendor":"Juniper Networks","product":"Junos OS","defaultStatus":"unaffected","versions":[{"version":"23.2R2-S2","status":"affected","lessThan":"23.2R2-S5","versionType":"semver"},{"version":"23.4R2-S1","status":"affected","lessThan":"23.4R2-S5","versionType":"semver"},{"version":"24.2","status":"affected","lessThan":"24.2R2-S2","versionType":"semver"},{"version":"24.4","status":"affected","lessThan":"24.4R1-S3, 24.4R2","versionType":"semver"}],"platforms":["SRX Series"]}],"references":["https://supportportal.juniper.net/JSA105996","https://kb.juniper.net/JSA105996"],"weaknesses":["CWE-1286"],"ingestedAt":"2026-10-29T20:11:10.572Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/21xxx/CVE-2026-21917.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-21917","state":"PUBLISHED","datePublished":"2026-01-15T20:27:11.214Z","dateUpdated":"2026-01-15T21:12:37.455Z","assignerShortName":"juniper","assignerOrgId":"8cbe9d5a-a066-4c94-8978-4b15efeae968","dateReserved":"2026-01-05T17:32:48.711Z"},"containers":{"cna":{"title":"Junos OS: SRX Series: Specifically malformed SSL packet causes FPC crash","descriptions":[{"lang":"en","value":"An Improper Validation of Syntactic Correctness of Input vulnerability in the Web-Filtering module of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS).\n\nIf an SRX device configured for UTM Web-Filtering receives a specifically malformed SSL packet, this will cause an FPC crash and restart.\nThis issue affects Junos OS on SRX Series:\n\n\n\n  *  23.2 versions from 23.2R2-S2 before 23.2R2-S5, \n  *  23.4 versions from 23.4R2-S1 before 23.4R2-S5,\n  *  24.2 versions before 24.2R2-S2,\n  *  24.4 versions before 24.4R1-S3, 24.4R2.\n\n\nEarlier versions of Junos are also affected, but no fix is available."}],"affected":[{"vendor":"Juniper Networks","product":"Junos OS","defaultStatus":"unaffected","versions":[{"version":"23.2R2-S2","status":"affected","lessThan":"23.2R2-S5","versionType":"semver"},{"version":"23.4R2-S1","status":"affected","lessThan":"23.4R2-S5","versionType":"semver"},{"version":"24.2","status":"affected","lessThan":"24.2R2-S2","versionType":"semver"},{"version":"24.4","status":"affected","lessThan":"24.4R1-S3, 24.4R2","versionType":"semver"}],"platforms":["SRX Series"]}],"references":[{"url":"https://supportportal.juniper.net/JSA105996","tags":["vendor-advisory"]},{"url":"https://kb.juniper.net/JSA105996","tags":["vendor-advisory"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]},{"cvssV4_0":{"Automatable":"YES","Recovery":"AUTOMATIC","Safety":"NOT_DEFINED","attackComplexity":"LOW","attackRequirements":"NONE","attackVector":"NETWORK","baseScore":8.7,"baseSeverity":"HIGH","privilegesRequired":"NONE","providerUrgency":"NOT_DEFINED","subAvailabilityImpact":"LOW","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","userInteraction":"NONE","valueDensity":"NOT_DEFINED","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/AU:Y/R:A/RE:M","version":"4.0","vulnAvailabilityImpact":"HIGH","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnerabilityResponseEffort":"MODERATE"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-1286","description":"CWE-1286 Improper Validation of Syntactic Correctness of Input","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"juniper","orgId":"8cbe9d5a-a066-4c94-8978-4b15efeae968","dateUpdated":"2026-01-15T20:27:11.214Z"},"configurations":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"To be exposed to this issue web-filtering needs to be configured as follows:<br><br><tt>[ security utm utm-policy &lt;utm policy name&gt; web-filtering&nbsp;http-profile &lt;name&gt; ]<br>[&nbsp;security policies ... policy &lt;security policy name&gt; then permit application-services utm-policy &lt;utm policy name&gt; ]</tt>"}],"value":"To be exposed to this issue web-filtering needs to be configured as follows:\n\n[ security utm utm-policy <utm policy name> web-filtering http-profile <name> ]\n[ security policies ... policy <security policy name> then permit application-services utm-policy <utm policy name> ]"}],"datePublic":"2026-01-14T17:00:00.000Z","exploits":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"Juniper SIRT is not aware of any malicious exploitation of this vulnerability."}],"value":"Juniper SIRT is not aware of any malicious exploitation of this vulnerability."}],"solutions":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"The following software releases have been updated to resolve this specific issue: 23.2R2-S5, 23.4R2-S5, 24.2R2-S2, 24.4R1-S3, 24.4R2, 25.2R1, and all subsequent releases."}],"value":"The following software releases have been updated to resolve this specific issue: 23.2R2-S5, 23.4R2-S5, 24.2R2-S2, 24.4R1-S3, 24.4R2, 25.2R1, and all subsequent releases."}],"source":{"advisory":"JSA105996","defect":["1876037"],"discovery":"INTERNAL"},"workarounds":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"There are no known workarounds for this issue."}],"value":"There are no known workarounds for this issue."}],"x_generator":{"engine":"Vulnogram 0.1.0-dev"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-01-15T21:12:30.579909Z","id":"CVE-2026-21917","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-01-15T21:12:37.455Z"}}]}}}