{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-103903", "assignerOrgId": "a6d3dc9e-0591-4a13-bce7-0f5b31ff6158", "state": "PUBLISHED", "assignerShortName": "ENISA", "dateReserved": "2026-10-01T14:12:50.876Z", "datePublished": "2026-10-12T10:37:23.578Z", "dateUpdated": "2026-10-12T10:37:23.578Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "a6d3dc9e-0591-4a13-bce7-0f5b31ff6158", "shortName": "ENISA", "dateUpdated": "2026-10-12T10:37:23.578Z"}, "title": "MikroTik RouterOS WinBox split-principal authentication bypass allows privilege escalation", "problemTypes": [{"descriptions": [{"lang": "en", "cweId": "CWE-863", "description": "CWE-863 Incorrect Authorization", "type": "CWE"}]}], "affected": [{"vendor": "MikroTik", "product": "RouterOS", "modules": ["WinBox authentication / user service"], "versions": [{"status": "affected", "version": "7.0.0", "lessThan": "7.24.5", "versionType": "semver"}, {"status": "unaffected", "version": "7.25rc1", "versionType": "custom"}], "defaultStatus": "affected"}], "descriptions": [{"lang": "en", "value": "An incorrect authorization vulnerability in the WinBox\nauthentication flow of MikroTik RouterOS allows a remote authenticated attacker\nwith credentials for a low-privilege account permitted to use WinBox to obtain\nthe authorization policy of a different existing account. The stage-one EC-SRP\nchallenge and proof are verified using the attacker's account, while the\nindependently supplied stage-two username is used to install the target\naccount's privileges. By specifying a higher-privilege account such as admin, a\nlow-privilege user can obtain a full administrative session without knowing the\ntarget account's password and can use that session to increase the privileges\nof the attacker's own account.", "supportingMedia": [{"type": "text/html", "base64": false, "value": "<span>An incorrect authorization vulnerability in the WinBox\nauthentication flow of MikroTik RouterOS allows a remote authenticated attacker\nwith credentials for a low-privilege account permitted to use WinBox to obtain\nthe authorization policy of a different existing account. The stage-one EC-SRP\nchallenge and proof are verified using the attacker's account, while the\nindependently supplied stage-two username is used to install the target\naccount's privileges. By specifying a higher-privilege account such as admin, a\nlow-privilege user can obtain a full administrative session without knowing the\ntarget account's password and can use that session to increase the privileges\nof the attacker's own account.</span>"}]}], "references": [{"url": "https://mikrotik.com/download/changelogs?channelFilter=stable&versionFilter=7.24.5", "name": "MikroTik RouterOS 7.24.5 stable release notes", "tags": ["release-notes"]}, {"url": "https://forum.mikrotik.com/t/7-25rc1-testing-is-released/27352", "tags": ["release-notes"]}, {"url": "https://br2sec.com/lv/resursi/2026-routeros-winbox-auth-bypass/", "tags": ["technical-description", "third-party-advisory"]}, {"url": "https://cvd.cert.lv/disclosed/vuln-all-709639748", "tags": ["government-resource"]}], "metrics": [{"format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}], "cvssV4_0": {"attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "LOW", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "subConfidentialityImpact": "NONE", "vulnIntegrityImpact": "HIGH", "subIntegrityImpact": "NONE", "vulnAvailabilityImpact": "HIGH", "subAvailabilityImpact": "NONE", "exploitMaturity": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "version": "4.0", "baseSeverity": "HIGH", "baseScore": 8.7, "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"}}, {"format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}], "cvssV3_1": {"version": "3.1", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH", "baseSeverity": "HIGH", "baseScore": 8.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}}], "workarounds": [{"lang": "en", "value": "Until upgrade, restrict the WinBox service to trusted\nmanagement addresses, remove the winbox policy from low-privilege accounts, or\ndisable WinBox. These measures reduce reachability but do not replace the fix.", "supportingMedia": [{"type": "text/html", "base64": false, "value": "<span>Until upgrade, restrict the WinBox service to trusted\nmanagement addresses, remove the winbox policy from low-privilege accounts, or\ndisable WinBox. These measures reduce reachability but do not replace the fix.</span>"}]}], "solutions": [{"lang": "en", "value": "Upgrade to RouterOS 7.24.5 stable, 7.25rc1 testing, or\na later vendor release containing the fix.", "supportingMedia": [{"type": "text/html", "base64": false, "value": "<span>Upgrade to RouterOS 7.24.5 stable, 7.25rc1 testing, or\na later vendor release containing the fix.</span>"}]}], "x_generator": {"engine": "Vulnogram 1.0.5"}, "source": {"discovery": "UNKNOWN"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "affected", "modules": ["WinBox authentication / user service"], "product": "RouterOS", "vendor": "MikroTik", "versions": [{"lessThan": "7.24.5", "status": "affected", "version": "7.0.0", "versionType": "semver"}, {"status": "unaffected", "version": "7.25rc1", "versionType": "custom"}]}], "source": "a6d3dc9e-0591-4a13-bce7-0f5b31ff6158"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "An incorrect authorization vulnerability in the WinBox\nauthentication flow of MikroTik RouterOS allows a remote authenticated attacker\nwith credentials for a low-privilege account permitted to use WinBox to obtain\nthe authorization policy of a different existing account. The stage-one EC-SRP\nchallenge and proof are verified using the attacker's account, while the\nindependently supplied stage-two username is used to install the target\naccount's privileges. By specifying a higher-privilege account such as admin, a\nlow-privilege user can obtain a full administrative session without knowing the\ntarget account's password and can use that session to increase the privileges\nof the attacker's own account."}], "id": "CVE-2026-103903", "lastModified": "2026-10-12T11:17:09.517", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 8.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 2.8, "impactScore": 5.9, "source": "a6d3dc9e-0591-4a13-bce7-0f5b31ff6158", "type": "Secondary"}], "cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 8.7, "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": "LOW", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "NONE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/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:X/R:X/V:X/RE:X/U:X", "version": "4.0", "vulnAvailabilityImpact": "HIGH", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "a6d3dc9e-0591-4a13-bce7-0f5b31ff6158", "type": "Secondary"}]}, "published": "2026-10-12T11:17:09.517", "references": [{"source": "a6d3dc9e-0591-4a13-bce7-0f5b31ff6158", "url": "https://br2sec.com/lv/resursi/2026-routeros-winbox-auth-bypass/"}, {"source": "a6d3dc9e-0591-4a13-bce7-0f5b31ff6158", "url": "https://cvd.cert.lv/disclosed/vuln-all-709639748"}, {"source": "a6d3dc9e-0591-4a13-bce7-0f5b31ff6158", "url": "https://forum.mikrotik.com/t/7-25rc1-testing-is-released/27352"}, {"source": "a6d3dc9e-0591-4a13-bce7-0f5b31ff6158", "url": "https://mikrotik.com/download/changelogs?channelFilter=stable&versionFilter=7.24.5"}], "sourceIdentifier": "a6d3dc9e-0591-4a13-bce7-0f5b31ff6158", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-863"}], "source": "a6d3dc9e-0591-4a13-bce7-0f5b31ff6158", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[7.0.0,7.24.5)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "7.25rc1"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "RouterOS", "source": "cna", "vendor": "MikroTik"}, "product": "routeros", "vendor": "mikrotik"}], "created": "2026-10-12T12:30:12.445303+00:00", "updated": "2026-10-12T12:30:12.732373+00:00", "vendors": ["mikrotik", "mikrotik$PRODUCT$routeros"]}