{"dataType":"CVE_RECORD","dataVersion":"5.1","cveMetadata":{"cveId":"CVE-2025-21594","assignerOrgId":"8cbe9d5a-a066-4c94-8978-4b15efeae968","state":"PUBLISHED","assignerShortName":"juniper","dateReserved":"2024-12-26T14:47:11.669Z","datePublished":"2025-04-09T19:49:41.391Z","dateUpdated":"2025-04-10T13:14:00.650Z"},"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","platforms":["MX Series"],"product":"Junos OS","vendor":"Juniper Networks","versions":[{"lessThan":"21.2R3-S8","status":"affected","version":"0","versionType":"semver"},{"lessThan":"21.4R3-S7","status":"affected","version":"21.4","versionType":"semver"},{"lessThan":"22.1R3-S6","status":"affected","version":"22.1","versionType":"semver"},{"lessThan":"22.2R3-S4","status":"affected","version":"22.2","versionType":"semver"},{"lessThan":"22.3R3-S3","status":"affected","version":"22.3","versionType":"semver"},{"lessThan":"22.4R3-S2","status":"affected","version":"22.4","versionType":"semver"},{"lessThan":"23.2R2-S1","status":"affected","version":"23.2","versionType":"semver"},{"lessThan":"23.4R1-S2, 23.4R2","status":"affected","version":"23.4","versionType":"semver"},{"lessThan":"20.2R1","status":"unaffected","version":"0","versionType":"semver"}]}],"configurations":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"This issue only occurs when below config is enabled:
[ set services service-set <*> softwire-options dslite-ipv6-prefix-length 56]
"}],"value":"This issue only occurs when below config is enabled:\n\n[ set services service-set <*> softwire-options dslite-ipv6-prefix-length 56]"}],"datePublic":"2025-04-09T16:00:00.000Z","descriptions":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"An Improper Check for Unusual or Exceptional Conditions vulnerability in the pfe (packet forwarding engine) of Juniper Networks Junos OS on MX Series causes a port within a pool to be blocked leading to Denial of Service (DoS).
In a DS-Lite (Dual-Stack Lite) and NAT (Network Address Translation) scenario, when crafted IPv6 traffic is received and prefix-length is set to 56, the ports assigned to the user will not be freed. Eventually, users cannot establish new connections. Affected FPC/PIC need to be manually restarted to recover.
Following is the command to identify the issue:
user@host> show services nat source port-block Host_IP External_IP Port_Block Ports_Used/ Block_State/ Range Ports_Total Left_Time(s) 2001:: x.x.x.x 58880-59391 256/256*1 Active/- >>>>>>>>port still used
This issue affects Junos OS on MX Series:
from 21.2 before 21.2R3-S8,
from 21.4 before 21.4R3-S7,
from 22.1 before 22.1R3-S6,
from 22.2 before 22.2R3-S4,
from 22.3 before 22.3R3-S3,
from 22.4 before 22.4R3-S2,
from 23.2 before 23.2R2-S1,
from 23.4 before 23.4R1-S2, 23.4R2.
This issue does not affect versions before 20.2R1.
"}],"value":"An Improper Check for Unusual or Exceptional Conditions vulnerability in the pfe (packet forwarding engine) of Juniper Networks Junos OS on MX Series causes a port within a pool to be blocked leading to Denial of Service (DoS).\n\nIn a DS-Lite (Dual-Stack Lite) and NAT (Network Address Translation) scenario, when crafted IPv6 traffic is received and prefix-length is set to 56, the ports assigned to the user will not be freed. Eventually, users cannot establish new connections. Affected FPC/PIC need to be manually restarted to recover.\nFollowing is the command to identify the issue: \n\n\n user@host> show services nat source port-block \n Host_IP External_IP Port_Block Ports_Used/ Block_State/\n Range Ports_Total Left_Time(s)\n 2001:: x.x.x.x 58880-59391 256/256*1 Active/- >>>>>>>>port still usedThis issue affects Junos OS on MX Series: \n\n * from 21.2 before 21.2R3-S8, \n * from 21.4 before 21.4R3-S7, \n * from 22.1 before 22.1R3-S6, \n * from 22.2 before 22.2R3-S4, \n * from 22.3 before 22.3R3-S3, \n * from 22.4 before 22.4R3-S2, \n * from 23.2 before 23.2R2-S1, \n * from 23.4 before 23.4R1-S2, 23.4R2.\n\n\nThis issue does not affect versions before 20.2R1."}],"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."}],"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":"NOT_DEFINED","Recovery":"USER","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/R:U","version":"4.0","vulnAvailabilityImpact":"HIGH","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnerabilityResponseEffort":"NOT_DEFINED"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-754","description":"CWE-754: Improper Check for Unusual or Exceptional Conditions","lang":"en","type":"CWE"}]}],"providerMetadata":{"orgId":"8cbe9d5a-a066-4c94-8978-4b15efeae968","shortName":"juniper","dateUpdated":"2025-04-09T19:49:41.391Z"},"references":[{"tags":["vendor-advisory"],"url":"https://supportportal.juniper.net/JSA96449"}],"solutions":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"The following software releases have been updated to resolve this specific issue:
Junos OS: 21.2R3-S8, 21.4R3-S7, 22.1R3-S6, 22.2R3-S4, 22.3R3-S3, 22.4R3-S2, 23.2R2-S1, 23.4R1-S2, 23.4R2, 24.2R1, and all subsequent releases."}],"value":"The following software releases have been updated to resolve this specific issue: \n\nJunos OS: 21.2R3-S8, 21.4R3-S7, 22.1R3-S6, 22.2R3-S4, 22.3R3-S3, 22.4R3-S2, 23.2R2-S1, 23.4R1-S2, 23.4R2, 24.2R1, and all subsequent releases."}],"source":{"advisory":"JSA96449","defect":["1785403"],"discovery":"USER"},"timeline":[{"lang":"en","time":"2025-04-09T16:00:00.000Z","value":"Initial Publication"}],"title":"Junos OS: MX Series: In DS-lite and NAT scenario receipt of crafted IPv6 traffic causes port block","workarounds":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"Modify the IPv6 prefix-length to be 64/96/128 through the command: [ set services service-set <*> softwire-options dslite-ipv6-prefix-length 64/96/128]"}],"value":"Modify the IPv6 prefix-length to be 64/96/128 through the command:\n\n[ set services service-set <*> softwire-options dslite-ipv6-prefix-length 64/96/128]"}],"x_generator":{"engine":"Vulnogram 0.1.0-dev"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2025-04-10T13:13:47.889505Z","id":"CVE-2025-21594","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2025-04-10T13:14:00.650Z"}}]}}