CVE-2026-89028

Summary

MikroTik RouterOS before 7.24 contains a heap memory corruption vulnerability in the userspace SMB daemon that allows remote attackers to corrupt adjacent heap memory by supplying a crafted uniPwdLen value in the SMB1 SessionSetupAndX handler. An attacker can send a malformed SMB1 request with a uniPwdLen field that triggers an integer underflow, causing the resulting value to be used as the copy length in a memory copy operation into a smaller heap buffer, corrupting adjacent heap memory.

Affected Software

VendorProductVersion RangeStatus
MikroTikRouterOS0 <= 6.49.18affected
MikroTikRouterOS7.0.0 <= 7.11.2affected
MikroTikRouterOS7.24.0unaffected

Weaknesses

  • CWE-122: Heap-based Buffer Overflow
  • CWE-191: Integer Underflow (Wrap or Wraparound)

References