{"id":"CVE-2026-33797","state":"PUBLISHED","title":"Junos OS and Junos OS Evolved: An attacker sending a specific genuine BGP packet causes a BGP reset","description":"An Improper Input Validation vulnerability in Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, adjacent attacker, sending a specific genuine BGP packet in an already established BGP session to reset only that session causing a Denial of Service (DoS).\n\nAn attacker repeatedly sending the packet will sustain the Denial of Service (DoS).This issue affects Junos OS:\n\n  *  25.2 versions before 25.2R2\n\n\nThis issue does not affect Junos OS versions before 25.2R1.\n\nThis issue affects Junos OS Evolved: \n  *  25.2-EVO versions before 25.2R2-EVO\n\n\nThis issue does not affect Junos OS Evolved versions before 25.2R1-EVO.\n\neBGP and iBGP are affected.\nIPv4 and IPv6 are affected.","publishedAt":"2026-04-09T21:31:22.902Z","updatedAt":"2026-04-23T20:08:35.655Z","severity":{"score":7.1,"label":"High","version":"4.0","vector":"CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/AU:Y/R:A/V:C/RE:M/U:Green","source":"juniper"},"assigner":"juniper","products":["Juniper Networks Junos OS","Juniper Networks Junos OS Evolved"],"affected":[{"vendor":"Juniper Networks","product":"Junos OS","defaultStatus":"unaffected","versions":[{"version":"25.2","status":"affected","lessThan":"25.2R2","versionType":"semver"},{"version":"0","status":"unaffected","lessThan":"25.2R1","versionType":"semver"}]},{"vendor":"Juniper Networks","product":"Junos OS Evolved","defaultStatus":"unaffected","versions":[{"version":"25.2","status":"affected","lessThan":"25.2R2-EVO","versionType":"semver"},{"version":"0","status":"unaffected","lessThan":"25.2R1-EVO","versionType":"semver"}],"modules":["bgp"]}],"references":["https://kb.juniper.net/JSA107850","https://supportportal.juniper.net/JSA107850"],"weaknesses":["CWE-20"],"ingestedAt":"2026-10-29T20:11:40.391Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/33xxx/CVE-2026-33797.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-33797","state":"PUBLISHED","datePublished":"2026-04-09T21:31:22.902Z","dateUpdated":"2026-04-23T20:08:35.655Z","assignerShortName":"juniper","assignerOrgId":"8cbe9d5a-a066-4c94-8978-4b15efeae968","dateReserved":"2026-03-23T19:46:13.673Z"},"containers":{"cna":{"title":"Junos OS and Junos OS Evolved: An attacker sending a specific genuine BGP packet causes a BGP reset","descriptions":[{"lang":"en","value":"An Improper Input Validation vulnerability in Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, adjacent attacker, sending a specific genuine BGP packet in an already established BGP session to reset only that session causing a Denial of Service (DoS).\n\nAn attacker repeatedly sending the packet will sustain the Denial of Service (DoS).This issue affects Junos OS:\n\n  *  25.2 versions before 25.2R2\n\n\nThis issue does not affect Junos OS versions before 25.2R1.\n\nThis issue affects Junos OS Evolved: \n  *  25.2-EVO versions before 25.2R2-EVO\n\n\nThis issue does not affect Junos OS Evolved versions before 25.2R1-EVO.\n\neBGP and iBGP are affected.\nIPv4 and IPv6 are affected."}],"affected":[{"vendor":"Juniper Networks","product":"Junos OS","defaultStatus":"unaffected","versions":[{"version":"25.2","status":"affected","lessThan":"25.2R2","versionType":"semver"},{"version":"0","status":"unaffected","lessThan":"25.2R1","versionType":"semver"}]},{"vendor":"Juniper Networks","product":"Junos OS Evolved","defaultStatus":"unaffected","versions":[{"version":"25.2","status":"affected","lessThan":"25.2R2-EVO","versionType":"semver"},{"version":"0","status":"unaffected","lessThan":"25.2R1-EVO","versionType":"semver"}],"modules":["bgp"]}],"references":[{"url":"https://kb.juniper.net/JSA107850","tags":["vendor-advisory"]},{"url":"https://supportportal.juniper.net/JSA107850","tags":["vendor-advisory"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"ADJACENT_NETWORK","availabilityImpact":"HIGH","baseScore":7.4,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"CHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/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":"ADJACENT","baseScore":7.1,"baseSeverity":"HIGH","privilegesRequired":"NONE","providerUrgency":"GREEN","subAvailabilityImpact":"LOW","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","userInteraction":"NONE","valueDensity":"CONCENTRATED","vectorString":"CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/AU:Y/R:A/V:C/RE:M/U:Green","version":"4.0","vulnAvailabilityImpact":"HIGH","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnerabilityResponseEffort":"MODERATE"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-20","description":"CWE-20 Improper Input Validation","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"juniper","orgId":"8cbe9d5a-a066-4c94-8978-4b15efeae968","dateUpdated":"2026-04-23T20:08:35.655Z"},"configurations":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"<tt>&nbsp; [ protocols bgp group &lt;group&gt; neighbor ]</tt><br>"}],"value":"[ protocols bgp group <group> neighbor ]"}],"datePublic":"2026-04-08T16:00:00.000Z","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:<br>Junos OS:&nbsp;25.2R2,&nbsp;25.4R1, and all subsequent releases.<br>Junos OS Evolved: 25.2R2-EVO, 25.4R1-EVO, and all subsequent releases."}],"value":"The following software releases have been updated to resolve this specific issue:\nJunos OS: 25.2R2, 25.4R1, and all subsequent releases.\nJunos OS Evolved: 25.2R2-EVO, 25.4R1-EVO, and all subsequent releases."}],"source":{"advisory":"JSA107850","defect":["1893316"],"discovery":"INTERNAL"},"workarounds":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"There are no known workarounds for this issue.<br>"}],"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":{"id":"CVE-2026-33797","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2026-04-13T17:40:25.675431Z"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-04-13T18:06:19.434Z"}}]}}}