CVE-2026-16347 (GCVE-0-2026-16347)
Vulnerability from cvelistv5
Published
2026-07-28 19:59
Modified
2026-07-29 13:57
Severity ?
8.8 (High) - CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
8.7 (High) - CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
8.7 (High) - CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
VLAI Severity ?
EPSS score ?
CWE
- CWE-307 - Improper restriction of excessive authentication attempts
Summary
MikroTik RouterOS contains a weakness in its API authentication handling that lacks effective safeguards against excessive login attempts. The system does not enforce meaningful rate-limiting, account lockout, or source-based restrictions, allowing repeated authentication failures to proceed without defensive response. In some versions, a fixed per-connection delay is present, but it can be bypassed through concurrent sessions, resulting in continued high-volume attempts. This deficiency increases the risk that an attacker could eventually obtain valid credentials and gain unauthorized access to administrative services.
References
| URL | Tags | ||||
|---|---|---|---|---|---|
|
|||||
Impacted products
| Vendor | Product | Version | |||||||
|---|---|---|---|---|---|---|---|---|---|
| MikroTik | RouterOS |
Version: All versions |
|||||||
|
|||||||||
{
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-16347",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "total"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-07-29T13:57:29.902200Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-07-29T13:57:56.713Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"defaultStatus": "affected",
"product": "RouterOS",
"vendor": "MikroTik",
"versions": [
{
"status": "affected",
"version": "All versions"
}
]
},
{
"defaultStatus": "affected",
"product": "Cloud Hosted Router",
"vendor": "MikroTik",
"versions": [
{
"status": "affected",
"version": "All versions"
}
]
}
],
"credits": [
{
"lang": "en",
"type": "finder",
"value": "Andre Santos of Uni\u00e3o Geek reported this vulnerability to CISA."
}
],
"descriptions": [
{
"lang": "en",
"supportingMedia": [
{
"base64": false,
"type": "text/html",
"value": "MikroTik RouterOS contains a weakness in its API authentication handling that lacks effective safeguards against excessive login attempts. The system does not enforce meaningful rate-limiting, account lockout, or source-based restrictions, allowing repeated authentication failures to proceed without defensive response. In some versions, a fixed per-connection delay is present, but it can be bypassed through concurrent sessions, resulting in continued high-volume attempts. This deficiency increases the risk that an attacker could eventually obtain valid credentials and gain unauthorized access to administrative services.\u0026nbsp;\u003cbr\u003e"
}
],
"value": "MikroTik RouterOS contains a weakness in its API authentication handling that lacks effective safeguards against excessive login attempts. The system does not enforce meaningful rate-limiting, account lockout, or source-based restrictions, allowing repeated authentication failures to proceed without defensive response. In some versions, a fixed per-connection delay is present, but it can be bypassed through concurrent sessions, resulting in continued high-volume attempts. This deficiency increases the risk that an attacker could eventually obtain valid credentials and gain unauthorized access to administrative services."
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "ADJACENT_NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 8.8,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"format": "CVSS",
"scenarios": [
{
"lang": "en",
"value": "GENERAL"
}
]
},
{
"cvssV4_0": {
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"attackComplexity": "LOW",
"attackRequirements": "NONE",
"attackVector": "ADJACENT",
"baseScore": 8.7,
"baseSeverity": "HIGH",
"exploitMaturity": "NOT_DEFINED",
"privilegesRequired": "NONE",
"providerUrgency": "NOT_DEFINED",
"subAvailabilityImpact": "NONE",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"userInteraction": "NONE",
"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
"version": "4.0",
"vulnAvailabilityImpact": "HIGH",
"vulnConfidentialityImpact": "HIGH",
"vulnIntegrityImpact": "HIGH",
"vulnerabilityResponseEffort": "NOT_DEFINED"
},
"format": "CVSS",
"scenarios": [
{
"lang": "en",
"value": "GENERAL"
}
]
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-307",
"description": "CWE-307 Improper restriction of excessive authentication attempts",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-07-28T19:59:29.927Z",
"orgId": "7d14cffa-0d7d-4270-9dc0-52cabd5a23a6",
"shortName": "icscert"
},
"references": [
{
"tags": [
"government-resource"
],
"url": "https://www.cisa.gov/news-events/ics-advisories/icsa-26-209-05"
}
],
"source": {
"discovery": "UNKNOWN"
},
"title": "Improper restriction of excessive authentication attempts in MikroTik RouterOS and Cloud Hosted Router",
"workarounds": [
{
"lang": "en",
"supportingMedia": [
{
"base64": false,
"type": "text/html",
"value": "No fix is currently available from MikroTik. Until a fix is available, MikroTik recommends that users adopt the following mitigations: Use a strong VPN or other additional protection layer if the API is exposed to public networks.\n\u003cbr\u003e* Configure the unsuccessful-attempt time range (0.1 to 0.5 seconds) in /ip service for all services, including the API, once available.\n\u003cbr\u003e* Connect initially from a trusted network (LAN) port only, then configure the router per your security requirements.\n\u003cbr\u003e* Restrict/limit access to management services from untrusted networks.\n\u003cbr\u003e* Apply firewall rules to control and restrict access to management services where possible.\n\u003cbr\u003e* Use long, randomly generated passwords rather than weak or default-simple ones, to keep the brute-force search space impractically large.\n\u003cbr\u003e* Keep the default randomly generated device password, or replace it with an equally strong one, since minimum complexity isn\u0027t enforced by default.\n\u003cbr\u003e\n\u003cbr\u003eUsers are encouraged to reach out to MikroTik (https://mikrotik.com/support) for further support.\u0026nbsp;"
}
],
"value": "No fix is currently available from MikroTik. Until a fix is available, MikroTik recommends that users adopt the following mitigations: Use a strong VPN or other additional protection layer if the API is exposed to public networks.\n\n* Configure the unsuccessful-attempt time range (0.1 to 0.5 seconds) in /ip service for all services, including the API, once available.\n\n* Connect initially from a trusted network (LAN) port only, then configure the router per your security requirements.\n\n* Restrict/limit access to management services from untrusted networks.\n\n* Apply firewall rules to control and restrict access to management services where possible.\n\n* Use long, randomly generated passwords rather than weak or default-simple ones, to keep the brute-force search space impractically large.\n\n* Keep the default randomly generated device password, or replace it with an equally strong one, since minimum complexity isn\u0027t enforced by default.\n\n\n\nUsers are encouraged to reach out to MikroTik (https://mikrotik.com/support) for further support."
}
],
"x_generator": {
"engine": "Vulnogram 1.0.4"
}
}
},
"cveMetadata": {
"assignerOrgId": "7d14cffa-0d7d-4270-9dc0-52cabd5a23a6",
"assignerShortName": "icscert",
"cveId": "CVE-2026-16347",
"datePublished": "2026-07-28T19:59:29.927Z",
"dateReserved": "2026-07-20T20:41:22.596Z",
"dateUpdated": "2026-07-29T13:57:56.713Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"vulnrichment": {
"containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-16347\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"total\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-07-29T13:57:29.902200Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-07-29T13:57:41.343Z\"}}], \"cna\": {\"title\": \"Improper restriction of excessive authentication attempts in MikroTik RouterOS and Cloud Hosted Router\", \"source\": {\"discovery\": \"UNKNOWN\"}, \"credits\": [{\"lang\": \"en\", \"type\": \"finder\", \"value\": \"Andre Santos of Uni\\u00e3o Geek reported this vulnerability to CISA.\"}], \"metrics\": [{\"format\": \"CVSS\", \"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 8.8, \"attackVector\": \"ADJACENT_NETWORK\", \"baseSeverity\": \"HIGH\", \"vectorString\": \"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H\", \"integrityImpact\": \"HIGH\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"HIGH\", \"privilegesRequired\": \"NONE\", \"confidentialityImpact\": \"HIGH\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"GENERAL\"}]}, {\"format\": \"CVSS\", \"cvssV4_0\": {\"Safety\": \"NOT_DEFINED\", \"version\": \"4.0\", \"Recovery\": \"NOT_DEFINED\", \"baseScore\": 8.7, \"Automatable\": \"NOT_DEFINED\", \"attackVector\": \"ADJACENT\", \"baseSeverity\": \"HIGH\", \"valueDensity\": \"NOT_DEFINED\", \"vectorString\": \"CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N\", \"exploitMaturity\": \"NOT_DEFINED\", \"providerUrgency\": \"NOT_DEFINED\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"attackRequirements\": \"NONE\", \"privilegesRequired\": \"NONE\", \"subIntegrityImpact\": \"NONE\", \"vulnIntegrityImpact\": \"HIGH\", \"subAvailabilityImpact\": \"NONE\", \"vulnAvailabilityImpact\": \"HIGH\", \"subConfidentialityImpact\": \"NONE\", \"vulnConfidentialityImpact\": \"HIGH\", \"vulnerabilityResponseEffort\": \"NOT_DEFINED\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"GENERAL\"}]}], \"affected\": [{\"vendor\": \"MikroTik\", \"product\": \"RouterOS\", \"versions\": [{\"status\": \"affected\", \"version\": \"All versions\"}], \"defaultStatus\": \"affected\"}, {\"vendor\": \"MikroTik\", \"product\": \"Cloud Hosted Router\", \"versions\": [{\"status\": \"affected\", \"version\": \"All versions\"}], \"defaultStatus\": \"affected\"}], \"references\": [{\"url\": \"https://www.cisa.gov/news-events/ics-advisories/icsa-26-209-05\", \"tags\": [\"government-resource\"]}], \"workarounds\": [{\"lang\": \"en\", \"value\": \"No fix is currently available from MikroTik. Until a fix is available, MikroTik recommends that users adopt the following mitigations: Use a strong VPN or other additional protection layer if the API is exposed to public networks.\\n\\n* Configure the unsuccessful-attempt time range (0.1 to 0.5 seconds) in /ip service for all services, including the API, once available.\\n\\n* Connect initially from a trusted network (LAN) port only, then configure the router per your security requirements.\\n\\n* Restrict/limit access to management services from untrusted networks.\\n\\n* Apply firewall rules to control and restrict access to management services where possible.\\n\\n* Use long, randomly generated passwords rather than weak or default-simple ones, to keep the brute-force search space impractically large.\\n\\n* Keep the default randomly generated device password, or replace it with an equally strong one, since minimum complexity isn\u0027t enforced by default.\\n\\n\\n\\nUsers are encouraged to reach out to MikroTik (https://mikrotik.com/support) for further support.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"No fix is currently available from MikroTik. Until a fix is available, MikroTik recommends that users adopt the following mitigations: Use a strong VPN or other additional protection layer if the API is exposed to public networks.\\n\u003cbr\u003e* Configure the unsuccessful-attempt time range (0.1 to 0.5 seconds) in /ip service for all services, including the API, once available.\\n\u003cbr\u003e* Connect initially from a trusted network (LAN) port only, then configure the router per your security requirements.\\n\u003cbr\u003e* Restrict/limit access to management services from untrusted networks.\\n\u003cbr\u003e* Apply firewall rules to control and restrict access to management services where possible.\\n\u003cbr\u003e* Use long, randomly generated passwords rather than weak or default-simple ones, to keep the brute-force search space impractically large.\\n\u003cbr\u003e* Keep the default randomly generated device password, or replace it with an equally strong one, since minimum complexity isn\u0027t enforced by default.\\n\u003cbr\u003e\\n\u003cbr\u003eUsers are encouraged to reach out to MikroTik (https://mikrotik.com/support) for further support.\u0026nbsp;\", \"base64\": false}]}], \"x_generator\": {\"engine\": \"Vulnogram 1.0.4\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"MikroTik RouterOS contains a weakness in its API authentication handling that lacks effective safeguards against excessive login attempts. The system does not enforce meaningful rate-limiting, account lockout, or source-based restrictions, allowing repeated authentication failures to proceed without defensive response. In some versions, a fixed per-connection delay is present, but it can be bypassed through concurrent sessions, resulting in continued high-volume attempts. This deficiency increases the risk that an attacker could eventually obtain valid credentials and gain unauthorized access to administrative services.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"MikroTik RouterOS contains a weakness in its API authentication handling that lacks effective safeguards against excessive login attempts. The system does not enforce meaningful rate-limiting, account lockout, or source-based restrictions, allowing repeated authentication failures to proceed without defensive response. In some versions, a fixed per-connection delay is present, but it can be bypassed through concurrent sessions, resulting in continued high-volume attempts. This deficiency increases the risk that an attacker could eventually obtain valid credentials and gain unauthorized access to administrative services.\u0026nbsp;\u003cbr\u003e\", \"base64\": false}]}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-307\", \"description\": \"CWE-307 Improper restriction of excessive authentication attempts\"}]}], \"providerMetadata\": {\"orgId\": \"7d14cffa-0d7d-4270-9dc0-52cabd5a23a6\", \"shortName\": \"icscert\", \"dateUpdated\": \"2026-07-28T19:59:29.927Z\"}}}",
"cveMetadata": "{\"cveId\": \"CVE-2026-16347\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-07-29T13:57:56.713Z\", \"dateReserved\": \"2026-07-20T20:41:22.596Z\", \"assignerOrgId\": \"7d14cffa-0d7d-4270-9dc0-52cabd5a23a6\", \"datePublished\": \"2026-07-28T19:59:29.927Z\", \"assignerShortName\": \"icscert\"}",
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
Loading…
Loading…
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
Loading…
Loading…