{
"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": "2026-10-13T11:57:50.805Z"
},
"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": "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."
}
]
}
],
"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": "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."
}
]
}
],
"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": "Upgrade to RouterOS 7.24.5 stable, 7.25rc1 testing, or\na later vendor release containing the fix."
}
]
}
],
"x_generator": {
"engine": "Vulnogram 1.0.5"
},
"source": {
"discovery": "UNKNOWN"
}
},
"adp": [
{
"metrics": [
{
"other": {
"type": "ssvc",
"content": {
"id": "CVE-2026-103903",
"role": "CISA Coordinator",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "total"
}
],
"version": "2.0.3",
"timestamp": "2026-10-13T03:55:34.306578Z"
}
}
}
],
"title": "CISA ADP Vulnrichment",
"providerMetadata": {
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP",
"dateUpdated": "2026-10-13T11:57:50.805Z"
}
}
]
}
}