CISA KEV catalog
Confirmed active exploitation.
Listed in CISA's catalog of Known Exploited Vulnerabilities: attackers are using it in real attacks. Patch it with priority.
- Name
- MikroTik RouterOS Stack-Based Buffer Overflow Vulnerability
- Added to catalog
- Remediation due date (US federal)
- Required action
- Apply updates per vendor instructions.
Description
A buffer overflow was found in the MikroTik RouterOS SMB service when processing NetBIOS session request messages. Remote attackers with access to the service can exploit this vulnerability and gain code execution on the system. The overflow occurs before authentication takes place, so it is possible for an unauthenticated remote attacker to exploit it. All architectures and all devices running RouterOS before versions 6.41.3/6.42rc27 are vulnerable.
Affected products
mikrotik: routeros
References9
- seclists.org/fulldisclosure/2018/Mar/38 ExploitMailing ListThird Party AdvisoryVDB Entry
- www.coresecurity.com/advisories/mikrotik-routeros-smb-buffer-ov… ExploitThird Party Advisory
- www.exploit-db.com/exploits/44290/ ExploitThird Party AdvisoryVDB Entry
- seclists.org/fulldisclosure/2018/Mar/38 ExploitMailing ListThird Party AdvisoryVDB Entry
- www.coresecurity.com/advisories/mikrotik-routeros-smb-buffer-ov… ExploitThird Party Advisory
- www.exploit-db.com/exploits/44290/ ExploitThird Party AdvisoryVDB Entry
- www.securityfocus.com/bid/103427 Third Party AdvisoryVDB Entry
- www.securityfocus.com/bid/103427 Third Party AdvisoryVDB Entry
- www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=… US Government Resource
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 66% percentile: 99 · as of 10 November 2026
- CWE
- CWE-119
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