CVE-2026-21911

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-21911", "assignerOrgId": "8cbe9d5a-a066-4c94-8978-4b15efeae968", "state": "PUBLISHED", "assignerShortName": "juniper", "dateReserved": "2026-01-05T17:32:48.710Z", "datePublished": "2026-01-15T20:23:54.924Z", "dateUpdated": "2026-01-15T20:51:32.531Z"}, "containers": {"cna": {"affected": [{"defaultStatus": "unaffected", "product": "Junos OS Evolved", "vendor": "Juniper Networks", "versions": [{"lessThan": "21.4R3-S7-EVO", "status": "affected", "version": "0", "versionType": "semver"}, {"lessThan": "22.2R3-S4-EVO", "status": "affected", "version": "22.2", "versionType": "semver"}, {"lessThan": "22.3R3-S3-EVO", "status": "affected", "version": "22.3", "versionType": "semver"}, {"lessThan": "22.4R3-S2-EVO", "status": "affected", "version": "22.4", "versionType": "semver"}, {"lessThan": "23.2R2-S1-EVO", "status": "affected", "version": "23.2", "versionType": "semver"}, {"lessThan": "23.4R1-S2-EVO, 23.4R2-EVO", "status": "affected", "version": "23.4", "versionType": "semver"}]}], "configurations": [{"lang": "en", "supportingMedia": [{"base64": false, "type": "text/html", "value": "This issue affects label-switched interfaces configured for VPLS. For example:<br><br><tt>[routing-instances &lt;name&gt; instance-type vpls]<br>[routing-instances &lt;name&gt; protocols vpls]</tt>"}], "value": "This issue affects label-switched interfaces configured for VPLS. For example:\n\n[routing-instances <name> instance-type vpls]\n[routing-instances <name> protocols vpls]"}], "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);\">An Incorrect Calculation vulnerability in the Layer 2 Control\n\n<span style=\"background-color: rgb(255, 255, 255);\">Protocol </span>\n\n Daemon (l2cpd) of Juniper Networks Junos OS Evolved allows an unauthenticated network-adjacent attacker flapping the management interface to cause the learning of new MACs over label-switched interfaces (LSI) to stop while generating a&nbsp;</span>flood of logs, resulting in high CPU usage.<br><br>When the issue is seen, the following log message will be generated:<br><br><tt>op:1 flag:0x6 mac:xx:xx:xx:xx:xx:xx bd:2 ifl:13302 reason:0(REASON_NONE) i-op:6(INTRNL_OP_HW_FORCE_DELETE) status:10 lstatus:10 err:26(GETIFBD_VALIDATE_FAILED) err-reason 4(IFBD_VALIDATE_FAIL_EPOCH_MISMATCH) hw_wr:0x4 ctxsync:0 fwdsync:0 rtt-id:51 p_ifl:0 fwd_nh:0 svlbnh:0 event:- smask:0x100000000 dmask:0x0 mplsmask 0x1 act:0x5800 extf:0x0 pfe-id 0 hw-notif-ifl 13302 programmed-ifl 4294967295 pseudo-vtep underlay-ifl-idx 0 stack:GET_MAC, ALLOCATE_MAC, GET_IFL, GET_IFF, GET_IFBD, STOP,</tt> <p><br></p><p>This issue affects Junos OS Evolved:&nbsp;</p><ul><li>all versions before 21.4R3-S7-EVO,&nbsp;</li><li>from 22.2 before 22.2R3-S4-EVO,&nbsp;</li><li>from 22.3 before 22.3R3-S3-EVO,&nbsp;</li><li>from 22.4 before 22.4R3-S2-EVO,&nbsp;</li><li>from 23.2 before 23.2R2-S1-EVO,&nbsp;</li><li>from 23.4 before 23.4R1-S2-EVO, 23.4R2-EVO.</li></ul>"}], "value": "An Incorrect Calculation vulnerability in the Layer 2 Control\n\nProtocol \n\n Daemon (l2cpd) of Juniper Networks Junos OS Evolved allows an unauthenticated network-adjacent attacker flapping the management interface to cause the learning of new MACs over label-switched interfaces (LSI) to stop while generating a\u00a0flood of logs, resulting in high CPU usage.\n\nWhen the issue is seen, the following log message will be generated:\n\nop:1 flag:0x6 mac:xx:xx:xx:xx:xx:xx bd:2 ifl:13302 reason:0(REASON_NONE) i-op:6(INTRNL_OP_HW_FORCE_DELETE) status:10 lstatus:10 err:26(GETIFBD_VALIDATE_FAILED) err-reason 4(IFBD_VALIDATE_FAIL_EPOCH_MISMATCH) hw_wr:0x4 ctxsync:0 fwdsync:0 rtt-id:51 p_ifl:0 fwd_nh:0 svlbnh:0 event:- smask:0x100000000 dmask:0x0 mplsmask 0x1 act:0x5800 extf:0x0 pfe-id 0 hw-notif-ifl 13302 programmed-ifl 4294967295 pseudo-vtep underlay-ifl-idx 0 stack:GET_MAC, ALLOCATE_MAC, GET_IFL, GET_IFF, GET_IFBD, STOP, \n\n\nThis issue affects Junos OS Evolved:\u00a0\n\n * all versions before 21.4R3-S7-EVO,\u00a0\n * from 22.2 before 22.2R3-S4-EVO,\u00a0\n * from 22.3 before 22.3R3-S3-EVO,\u00a0\n * from 22.4 before 22.4R3-S2-EVO,\u00a0\n * from 23.2 before 23.2R2-S1-EVO,\u00a0\n * from 23.4 before 23.4R1-S2-EVO, 23.4R2-EVO."}], "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": "ADJACENT_NETWORK", "availabilityImpact": "HIGH", "baseScore": 6.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:A/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": "ADJACENT", "baseScore": 7.1, "baseSeverity": "HIGH", "privilegesRequired": "NONE", "providerUrgency": "AMBER", "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:Amber", "version": "4.0", "vulnAvailabilityImpact": "HIGH", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "vulnerabilityResponseEffort": "MODERATE"}, "format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "problemTypes": [{"descriptions": [{"cweId": "CWE-682", "description": "CWE-682 Incorrect Calculation", "lang": "en", "type": "CWE"}]}], "providerMetadata": {"orgId": "8cbe9d5a-a066-4c94-8978-4b15efeae968", "shortName": "juniper", "dateUpdated": "2026-01-15T20:23:54.924Z"}, "references": [{"tags": ["vendor-advisory"], "url": "https://supportportal.juniper.net/JSA106010"}, {"tags": ["vendor-advisory"], "url": "https://kb.juniper.net/JSA106010"}], "solutions": [{"lang": "en", "supportingMedia": [{"base64": false, "type": "text/html", "value": "The following software releases have been updated to resolve this specific issue: 21.4R3-S7-EVO, 22.2R3-S4-EVO, 22.3R3-S3-EVO, 22.4R3-S2-EVO, 23.2R2-S1-EVO, 23.4R1-S2-EVO, 23.4R2-EVO, 24.2R1-EVO, and all subsequent releases."}], "value": "The following software releases have been updated to resolve this specific issue: 21.4R3-S7-EVO, 22.2R3-S4-EVO, 22.3R3-S3-EVO, 22.4R3-S2-EVO, 23.2R2-S1-EVO, 23.4R1-S2-EVO, 23.4R2-EVO, 24.2R1-EVO, and all subsequent releases."}], "source": {"advisory": "JSA106010", "defect": ["1802153"], "discovery": "USER"}, "title": "Junos OS Evolved: Flapping management interface causes MAC learning on label-switched interfaces to stop", "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": [{"metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-01-15T20:51:26.965443Z", "id": "CVE-2026-21911", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"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": "2026-01-15T20:51:32.531Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-21911", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-01-15T20:51:26.965443Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-01-15T20:51:29.799Z"}}], "cna": {"title": "Junos OS Evolved: Flapping management interface causes MAC learning on label-switched interfaces to stop", "source": {"defect": ["1802153"], "advisory": "JSA106010", "discovery": "USER"}, "metrics": [{"format": "CVSS", "cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 6.5, "attackVector": "ADJACENT_NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "scenarios": [{"lang": "en", "value": "GENERAL"}]}, {"format": "CVSS", "cvssV4_0": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "AUTOMATIC", "baseScore": 7.1, "Automatable": "YES", "attackVector": "ADJACENT", "baseSeverity": "HIGH", "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:Amber", "providerUrgency": "AMBER", "userInteraction": "NONE", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "NONE", "subAvailabilityImpact": "LOW", "vulnAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "NONE", "vulnerabilityResponseEffort": "MODERATE"}, "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "affected": [{"vendor": "Juniper Networks", "product": "Junos OS Evolved", "versions": [{"status": "affected", "version": "0", "lessThan": "21.4R3-S7-EVO", "versionType": "semver"}, {"status": "affected", "version": "22.2", "lessThan": "22.2R3-S4-EVO", "versionType": "semver"}, {"status": "affected", "version": "22.3", "lessThan": "22.3R3-S3-EVO", "versionType": "semver"}, {"status": "affected", "version": "22.4", "lessThan": "22.4R3-S2-EVO", "versionType": "semver"}, {"status": "affected", "version": "23.2", "lessThan": "23.2R2-S1-EVO", "versionType": "semver"}, {"status": "affected", "version": "23.4", "lessThan": "23.4R1-S2-EVO, 23.4R2-EVO", "versionType": "semver"}], "defaultStatus": "unaffected"}], "exploits": [{"lang": "en", "value": "Juniper SIRT is not aware of any malicious exploitation of this vulnerability.", "supportingMedia": [{"type": "text/html", "value": "Juniper SIRT is not aware of any malicious exploitation of this vulnerability.", "base64": false}]}], "solutions": [{"lang": "en", "value": "The following software releases have been updated to resolve this specific issue: 21.4R3-S7-EVO, 22.2R3-S4-EVO, 22.3R3-S3-EVO, 22.4R3-S2-EVO, 23.2R2-S1-EVO, 23.4R1-S2-EVO, 23.4R2-EVO, 24.2R1-EVO, and all subsequent releases.", "supportingMedia": [{"type": "text/html", "value": "The following software releases have been updated to resolve this specific issue: 21.4R3-S7-EVO, 22.2R3-S4-EVO, 22.3R3-S3-EVO, 22.4R3-S2-EVO, 23.2R2-S1-EVO, 23.4R1-S2-EVO, 23.4R2-EVO, 24.2R1-EVO, and all subsequent releases.", "base64": false}]}], "datePublic": "2026-01-14T17:00:00.000Z", "references": [{"url": "https://supportportal.juniper.net/JSA106010", "tags": ["vendor-advisory"]}, {"url": "https://kb.juniper.net/JSA106010", "tags": ["vendor-advisory"]}], "workarounds": [{"lang": "en", "value": "There are no known workarounds for this issue.", "supportingMedia": [{"type": "text/html", "value": "There are no known workarounds for this issue.<br>", "base64": false}]}], "x_generator": {"engine": "Vulnogram 0.1.0-dev"}, "descriptions": [{"lang": "en", "value": "An Incorrect Calculation vulnerability in the Layer 2 Control\n\nProtocol \n\n Daemon (l2cpd) of Juniper Networks Junos OS Evolved allows an unauthenticated network-adjacent attacker flapping the management interface to cause the learning of new MACs over label-switched interfaces (LSI) to stop while generating a\u00a0flood of logs, resulting in high CPU usage.\n\nWhen the issue is seen, the following log message will be generated:\n\nop:1 flag:0x6 mac:xx:xx:xx:xx:xx:xx bd:2 ifl:13302 reason:0(REASON_NONE) i-op:6(INTRNL_OP_HW_FORCE_DELETE) status:10 lstatus:10 err:26(GETIFBD_VALIDATE_FAILED) err-reason 4(IFBD_VALIDATE_FAIL_EPOCH_MISMATCH) hw_wr:0x4 ctxsync:0 fwdsync:0 rtt-id:51 p_ifl:0 fwd_nh:0 svlbnh:0 event:- smask:0x100000000 dmask:0x0 mplsmask 0x1 act:0x5800 extf:0x0 pfe-id 0 hw-notif-ifl 13302 programmed-ifl 4294967295 pseudo-vtep underlay-ifl-idx 0 stack:GET_MAC, ALLOCATE_MAC, GET_IFL, GET_IFF, GET_IFBD, STOP, \n\n\nThis issue affects Junos OS Evolved:\u00a0\n\n * all versions before 21.4R3-S7-EVO,\u00a0\n * from 22.2 before 22.2R3-S4-EVO,\u00a0\n * from 22.3 before 22.3R3-S3-EVO,\u00a0\n * from 22.4 before 22.4R3-S2-EVO,\u00a0\n * from 23.2 before 23.2R2-S1-EVO,\u00a0\n * from 23.4 before 23.4R1-S2-EVO, 23.4R2-EVO.", "supportingMedia": [{"type": "text/html", "value": "<span style=\"background-color: rgb(255, 255, 255);\">An Incorrect Calculation vulnerability in the Layer 2 Control\n\n<span style=\"background-color: rgb(255, 255, 255);\">Protocol </span>\n\n Daemon (l2cpd) of Juniper Networks Junos OS Evolved allows an unauthenticated network-adjacent attacker flapping the management interface to cause the learning of new MACs over label-switched interfaces (LSI) to stop while generating a&nbsp;</span>flood of logs, resulting in high CPU usage.<br><br>When the issue is seen, the following log message will be generated:<br><br><tt>op:1 flag:0x6 mac:xx:xx:xx:xx:xx:xx bd:2 ifl:13302 reason:0(REASON_NONE) i-op:6(INTRNL_OP_HW_FORCE_DELETE) status:10 lstatus:10 err:26(GETIFBD_VALIDATE_FAILED) err-reason 4(IFBD_VALIDATE_FAIL_EPOCH_MISMATCH) hw_wr:0x4 ctxsync:0 fwdsync:0 rtt-id:51 p_ifl:0 fwd_nh:0 svlbnh:0 event:- smask:0x100000000 dmask:0x0 mplsmask 0x1 act:0x5800 extf:0x0 pfe-id 0 hw-notif-ifl 13302 programmed-ifl 4294967295 pseudo-vtep underlay-ifl-idx 0 stack:GET_MAC, ALLOCATE_MAC, GET_IFL, GET_IFF, GET_IFBD, STOP,</tt> <p><br></p><p>This issue affects Junos OS Evolved:&nbsp;</p><ul><li>all versions before 21.4R3-S7-EVO,&nbsp;</li><li>from 22.2 before 22.2R3-S4-EVO,&nbsp;</li><li>from 22.3 before 22.3R3-S3-EVO,&nbsp;</li><li>from 22.4 before 22.4R3-S2-EVO,&nbsp;</li><li>from 23.2 before 23.2R2-S1-EVO,&nbsp;</li><li>from 23.4 before 23.4R1-S2-EVO, 23.4R2-EVO.</li></ul>", "base64": false}]}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-682", "description": "CWE-682 Incorrect Calculation"}]}], "configurations": [{"lang": "en", "value": "This issue affects label-switched interfaces configured for VPLS. For example:\n\n[routing-instances <name> instance-type vpls]\n[routing-instances <name> protocols vpls]", "supportingMedia": [{"type": "text/html", "value": "This issue affects label-switched interfaces configured for VPLS. For example:<br><br><tt>[routing-instances &lt;name&gt; instance-type vpls]<br>[routing-instances &lt;name&gt; protocols vpls]</tt>", "base64": false}]}], "providerMetadata": {"orgId": "8cbe9d5a-a066-4c94-8978-4b15efeae968", "shortName": "juniper", "dateUpdated": "2026-01-15T20:23:54.924Z"}}}, "cveMetadata": {"cveId": "CVE-2026-21911", "state": "PUBLISHED", "dateUpdated": "2026-01-15T20:51:32.531Z", "dateReserved": "2026-01-05T17:32:48.710Z", "assignerOrgId": "8cbe9d5a-a066-4c94-8978-4b15efeae968", "datePublished": "2026-01-15T20:23:54.924Z", "assignerShortName": "juniper"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Junos OS Evolved", "vendor": "Juniper Networks", "versions": [{"lessThan": "21.4R3-S7-EVO", "status": "affected", "version": "0", "versionType": "semver"}, {"lessThan": "22.2R3-S4-EVO", "status": "affected", "version": "22.2", "versionType": "semver"}, {"lessThan": "22.3R3-S3-EVO", "status": "affected", "version": "22.3", "versionType": "semver"}, {"lessThan": "22.4R3-S2-EVO", "status": "affected", "version": "22.4", "versionType": "semver"}, {"lessThan": "23.2R2-S1-EVO", "status": "affected", "version": "23.2", "versionType": "semver"}, {"lessThan": "23.4R1-S2-EVO, 23.4R2-EVO", "status": "affected", "version": "23.4", "versionType": "semver"}]}], "source": "sirt@juniper.net"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:juniper:junos_os_evolved:*:*:*:*:*:*:*:*", "matchCriteriaId": "A51696D6-8503-4CBD-AD19-861E5BE94ED4", "versionEndExcluding": "21.4", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:21.4:-:*:*:*:*:*:*", "matchCriteriaId": "2E907193-075E-45BC-9257-9607DB790D71", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:21.4:r1:*:*:*:*:*:*", "matchCriteriaId": "8B73A41D-3FF5-4E53-83FF-74DF58E0D6C3", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:21.4:r1-s1:*:*:*:*:*:*", "matchCriteriaId": "CEDF46A8-FC3A-4779-B695-2CA11D045AEB", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:21.4:r1-s2:*:*:*:*:*:*", "matchCriteriaId": "39809219-9F87-4583-9DAD-9415DD320B36", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:21.4:r2:*:*:*:*:*:*", "matchCriteriaId": "DB299492-A919-4EBA-A62A-B3CF02FC0A95", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:21.4:r2-s1:*:*:*:*:*:*", "matchCriteriaId": "74ED0939-D5F8-4334-9838-40F29DE3597F", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:21.4:r2-s2:*:*:*:*:*:*", "matchCriteriaId": "C6937069-8C19-4B01-8415-ED7E9EAE2CE2", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:21.4:r3:*:*:*:*:*:*", "matchCriteriaId": "97DB6DD5-F5DD-4AE1-AF2F-8DB9E18FF882", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:21.4:r3-s1:*:*:*:*:*:*", "matchCriteriaId": "21DF05B8-EF7E-422F-8831-06904160714C", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:21.4:r3-s2:*:*:*:*:*:*", "matchCriteriaId": "492FCE45-68A1-4378-85D4-C4034FE0D836", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:21.4:r3-s3:*:*:*:*:*:*", "matchCriteriaId": "522114CC-1505-4205-B4B8-797DE1BD833B", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:21.4:r3-s4:*:*:*:*:*:*", "matchCriteriaId": "C9D664AB-0FA7-49C7-B6E1-69C77652FBEF", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:21.4:r3-s5:*:*:*:*:*:*", "matchCriteriaId": "9DB01252-2F11-41DB-9023-C74FD723334E", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:21.4:r3-s6:*:*:*:*:*:*", "matchCriteriaId": "F91450D5-F8CE-42EA-BB7E-312FCE024CD1", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.2:-:*:*:*:*:*:*", "matchCriteriaId": "A3CA3365-F9AF-40DF-8700-30AD4BC58E27", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.2:r1:*:*:*:*:*:*", "matchCriteriaId": "D77A072D-350A-42F2-8324-7D3AC1711BF9", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.2:r1-s1:*:*:*:*:*:*", "matchCriteriaId": "83AE395C-A651-4568-88E3-3600544BF799", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.2:r1-s2:*:*:*:*:*:*", "matchCriteriaId": "C7FEFD0A-A969-4F53-8668-1231FD675D6F", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.2:r2:*:*:*:*:*:*", "matchCriteriaId": "B3BE1FD4-DAD9-4357-A2E9-20E5826B0D5C", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.2:r2-s1:*:*:*:*:*:*", "matchCriteriaId": "81CC3480-4B65-4588-8D46-FA80A8F6D143", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.2:r2-s2:*:*:*:*:*:*", "matchCriteriaId": "F7E76F5F-DB37-4B7F-9247-3CEB4EBD7696", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.2:r3:*:*:*:*:*:*", "matchCriteriaId": "C63DBEE5-B0C2-498F-A672-B6596C89B0A2", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.2:r3-s1:*:*:*:*:*:*", "matchCriteriaId": "9370C46D-3AA1-4562-B67F-DF6EA10F209B", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.2:r3-s2:*:*:*:*:*:*", "matchCriteriaId": "1FD8C240-A7FE-4FD5-ADCC-289C1BC461BF", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.2:r3-s3:*:*:*:*:*:*", "matchCriteriaId": "2FB9F20B-7683-4B0D-8D2B-5569414EBC29", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.3:-:*:*:*:*:*:*", "matchCriteriaId": "BE2EF84D-55A9-41DC-A324-69E1DC426D0B", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.3:r1:*:*:*:*:*:*", "matchCriteriaId": "433631CA-3AC4-4D66-9B46-AEA4209347F1", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.3:r1-s1:*:*:*:*:*:*", "matchCriteriaId": "6E4CD8AD-277A-4FC5-A102-3E151060C216", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.3:r1-s2:*:*:*:*:*:*", "matchCriteriaId": "4BC09BAC-83E7-48CE-B571-ED49277B2987", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.3:r2:*:*:*:*:*:*", "matchCriteriaId": "FA4481D2-F693-48A5-8DBC-E86430987A25", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.3:r2-s1:*:*:*:*:*:*", "matchCriteriaId": "136CA584-2475-4A14-9771-F367180201D4", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.3:r2-s2:*:*:*:*:*:*", "matchCriteriaId": "4546776C-A657-42E3-9A36-47F9F59A88AD", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.3:r3:*:*:*:*:*:*", "matchCriteriaId": "156DD8ED-CE6E-48C0-9E67-16B04767D62E", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.3:r3-s1:*:*:*:*:*:*", "matchCriteriaId": "10F9C2B1-BD81-4EDC-ADF5-4B0F39001C7A", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.3:r3-s2:*:*:*:*:*:*", "matchCriteriaId": "61F649B0-0121-4760-9432-5F57214EFC2B", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.4:-:*:*:*:*:*:*", "matchCriteriaId": "0A33C425-921F-4795-B834-608C8F1597E0", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.4:r1:*:*:*:*:*:*", "matchCriteriaId": "93887799-F62C-4A4A-BCF5-004D0B4D4154", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.4:r1-s1:*:*:*:*:*:*", "matchCriteriaId": "62C473D2-2612-4480-82D8-8A24D0687BBD", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.4:r1-s2:*:*:*:*:*:*", "matchCriteriaId": "7FB4C5CA-A709-4B13-A9E0-372098A72AD3", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.4:r2:*:*:*:*:*:*", "matchCriteriaId": "04CE952D-E3C1-4B34-9E65-EC52BFE887AB", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.4:r2-s1:*:*:*:*:*:*", "matchCriteriaId": "8AE9D1A7-4721-4E1D-B965-FDC38126B1DD", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.4:r2-s2:*:*:*:*:*:*", "matchCriteriaId": "A8643AA3-29EF-48A7-B033-CB60988E214B", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.4:r3:*:*:*:*:*:*", "matchCriteriaId": "9800BA03-E6BF-4212-B2E7-69C0FD27D294", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:22.4:r3-s1:*:*:*:*:*:*", "matchCriteriaId": "ACCA655D-C542-44F1-B183-4C864CFF2D4F", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:23.2:-:*:*:*:*:*:*", "matchCriteriaId": "6DEAA7FD-385F-4221-907E-65ABC16BE4BE", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:23.2:r1:*:*:*:*:*:*", "matchCriteriaId": "DDEC008A-3137-48D1-8ABC-6DB0EFC40E50", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:23.2:r1-s1:*:*:*:*:*:*", "matchCriteriaId": "558D234D-BC50-415F-86D6-8E19D6C3ACE0", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:23.2:r1-s2:*:*:*:*:*:*", "matchCriteriaId": "33F4EEEE-77E9-4973-A770-99E7BA2F05F5", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:23.2:r2:*:*:*:*:*:*", "matchCriteriaId": "A4BB6910-B994-45FD-8153-5EC00EE842E6", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:23.4:-:*:*:*:*:*:*", "matchCriteriaId": "9D7F0D73-85EE-4A07-B51B-6BF52ECBA75E", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:23.4:r1:*:*:*:*:*:*", "matchCriteriaId": "FE777A1F-9CD9-426E-AF1C-FBE01EB9A4A8", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:23.4:r1-s1:*:*:*:*:*:*", "matchCriteriaId": "7147BA60-30A5-4CED-9AAF-F6BEA0528B89", "vulnerable": true}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:23.4:r2:*:*:*:*:*:*", "matchCriteriaId": "FB82B22F-9005-4EF0-A1E3-4261757783D4", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "An Incorrect Calculation vulnerability in the Layer 2 Control\n\nProtocol \n\n Daemon (l2cpd) of Juniper Networks Junos OS Evolved allows an unauthenticated network-adjacent attacker flapping the management interface to cause the learning of new MACs over label-switched interfaces (LSI) to stop while generating a\u00a0flood of logs, resulting in high CPU usage.\n\nWhen the issue is seen, the following log message will be generated:\n\nop:1 flag:0x6 mac:xx:xx:xx:xx:xx:xx bd:2 ifl:13302 reason:0(REASON_NONE) i-op:6(INTRNL_OP_HW_FORCE_DELETE) status:10 lstatus:10 err:26(GETIFBD_VALIDATE_FAILED) err-reason 4(IFBD_VALIDATE_FAIL_EPOCH_MISMATCH) hw_wr:0x4 ctxsync:0 fwdsync:0 rtt-id:51 p_ifl:0 fwd_nh:0 svlbnh:0 event:- smask:0x100000000 dmask:0x0 mplsmask 0x1 act:0x5800 extf:0x0 pfe-id 0 hw-notif-ifl 13302 programmed-ifl 4294967295 pseudo-vtep underlay-ifl-idx 0 stack:GET_MAC, ALLOCATE_MAC, GET_IFL, GET_IFF, GET_IFBD, STOP, \n\n\nThis issue affects Junos OS Evolved:\u00a0\n\n * all versions before 21.4R3-S7-EVO,\u00a0\n * from 22.2 before 22.2R3-S4-EVO,\u00a0\n * from 22.3 before 22.3R3-S3-EVO,\u00a0\n * from 22.4 before 22.4R3-S2-EVO,\u00a0\n * from 23.2 before 23.2R2-S1-EVO,\u00a0\n * from 23.4 before 23.4R1-S2-EVO, 23.4R2-EVO."}, {"lang": "es", "value": "Una vulnerabilidad de c\u00e1lculo incorrecto en el demonio del protocolo de control de capa 2 (l2cpd) de Juniper Networks Junos OS Evolved permite a un atacante adyacente a la red no autenticado que alterna la interfaz de gesti\u00f3n detener el aprendizaje de nuevas MAC a trav\u00e9s de interfaces conmutadas por etiquetas (LSI) mientras genera una inundaci\u00f3n de registros, lo que resulta en un alto uso de la CPU.\n\nCuando se observa el problema, se generar\u00e1 el siguiente mensaje de registro:\n\nop:1 flag:0x6 mac:xx:xx:xx:xx:xx:xx bd:2 ifl:13302 reason:0(REASON_NONE) i-op:6(INTRNL_OP_HW_FORCE_DELETE) status:10 lstatus:10 err:26(GETIFBD_VALIDATE_FAILED) err-reason 4(IFBD_VALIDATE_FAIL_EPOCH_MISMATCH) hw_wr:0x4 ctxsync:0 fwdsync:0 rtt-id:51 p_ifl:0 fwd_nh:0 svlbnh:0 event:- smask:0x100000000 dmask:0x0 mplsmask 0x1 act:0x5800 extf:0x0 pfe-id 0 hw-notif-ifl 13302 programmed-ifl 4294967295 pseudo-vtep underlay-ifl-idx 0 stack:GET_MAC, ALLOCATE_MAC, GET_IFL, GET_IFF, GET_IFBD, STOP,\n\nEste problema afecta a Junos OS Evolved:\n\n * todas las versiones anteriores a 21.4R3-S7-EVO,\n * desde 22.2 anteriores a 22.2R3-S4-EVO,\n * desde 22.3 anteriores a 22.3R3-S3-EVO,\n * desde 22.4 anteriores a 22.4R3-S2-EVO,\n * desde 23.2 anteriores a 23.2R2-S1-EVO,\n * desde 23.4 anteriores a 23.4R1-S2-EVO, 23.4R2-EVO."}], "id": "CVE-2026-21911", "lastModified": "2026-06-17T10:19:08.587", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "ADJACENT_NETWORK", "availabilityImpact": "HIGH", "baseScore": 6.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 2.8, "impactScore": 3.6, "source": "sirt@juniper.net", "type": "Secondary"}], "cvssMetricV40": [{"cvssData": {"Automatable": "YES", "Recovery": "AUTOMATIC", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "ADJACENT", "availabilityRequirement": "NOT_DEFINED", "baseScore": 7.1, "baseSeverity": "HIGH", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "NONE", "providerUrgency": "AMBER", "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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:A/V:C/RE:M/U:Amber", "version": "4.0", "vulnAvailabilityImpact": "HIGH", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "vulnerabilityResponseEffort": "MODERATE"}, "source": "sirt@juniper.net", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-21911", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-01-15T20:51:26.965443Z", "version": "2.0.3"}}]}, "published": "2026-01-15T21:16:07.110", "references": [{"source": "sirt@juniper.net", "tags": ["Vendor Advisory"], "url": "https://kb.juniper.net/JSA106010"}, {"source": "sirt@juniper.net", "tags": ["Vendor Advisory"], "url": "https://supportportal.juniper.net/JSA106010"}], "sourceIdentifier": "sirt@juniper.net", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-682"}], "source": "sirt@juniper.net", "type": "Secondary"}]}

{}

{"analysis": {"en": {"generated_at": "2026-04-18T05:57:49.637121+00:00", "value": {"mitigation_remediation": ["Update Junos\u00a0OS\u00a0Evolved to version 21.4R3\u2011S7\u2011EVO or any later patched release as listed by Juniper", "Back up the device configuration before performing the upgrade and verify the integrity afterward", "Limit access to the management interface by isolating it on a trusted VLAN or restricting it to known administrators; consider disabling SNMP/SSH on the interface if it is not required"], "summary": {"action": "Immediate Patch", "impact": "Denial of Service via resource exhaustion"}, "threat_synthesis": {"affected_systems": "All Junos\u00a0OS Evolved releases before 21.4R3\u2011S7\u2011EVO, before 22.2R3\u2011S4\u2011EVO, before 22.3R3\u2011S3\u2011EVO, before 22.4R3\u2011S2\u2011EVO, before 23.2R2\u2011S1\u2011EVO, and before 23.4R1\u2011S2\u2011EVO/23.4R2\u2011EVO. The official solution lists patched releases 21.4R3\u2011S7\u2011EVO, 22.2R3\u2011S4\u2011EVO, 22.3R3\u2011S3\u2011EVO, 22.4R3\u2011S2\u2011EVO, 23.2R2\u2011S1\u2011EVO, 23.4R1\u2011S2\u2011EVO, 23.4R2\u2011EVO, 24.2R1\u2011EVO and all later revisions.", "description_and_impact": "An incorrect calculation in the Layer\u00a02 Control Daemon (l2cpd) of Juniper Networks Junos\u00a0OS Evolved lets an unauthenticated, network\u2011adjacent attacker repeatedly enable and disable the device\u2019s management interface\u2014known as flapping. This exploitation stops the learning of new MAC addresses on label\u2011switched interfaces, while flooding system logs and generating sustained high CPU usage. The result is a denial\u2011of\u2011service condition that can compromise normal traffic handling on the affected device. The vulnerability is classified as CWE\u2011682 (Incorrect\u00a0Calculation).", "risk_and_exploitability": "The CVSS score of 7.1 indicates medium\u2011high severity, while the EPSS score of less than 1% suggests a low likelihood of exploitation in the wild. The vulnerability is not listed in CISA\u2019s KEV catalog, and no widespread exploits have been reported. Because the attack requires only local network proximity and no authentication, any device with the vulnerable management interface exposed to an untrusted segment faces elevated risk. An attacker that can cause the interface to flap is able to deny service without needing privileged credentials."}}}}, "created": "2026-01-16T13:43:11.884002+00:00", "updated": "2026-04-18T06:00:08.507535+00:00", "vendors": ["juniper_networks", "juniper_networks$PRODUCT$junos_os_evolved"]}