CVE-2026-89028: high-severity vulnerability in MikroTik RouterOS
MikroTik RouterOS < 7.24 Heap Corruption via SMB1 SessionSetupAndX
Published · Updated
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.2epss 0.6%
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.
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Affected products
MikroTik · RouterOSRelated CVEs — MikroTik RouterOS
In the same product, most dangerous first.
CVE-2019-3943—CVE-2019-3943EPSS 3.7%CVE-2023-30800HIGHMikroTik RouterOS Web Interface Heap CorruptionEPSS 1.7%CVE-2023-30799CRITICALMikroTik RouterOS Administrator Privilege EscalationEPSS 1.4%CVE-2025-10948HIGHMikroTik RouterOS libjson.so print parse_json_element buffer overflowEPSS 1.0%CVE-2026-84411CRITICALMikroTik RouterOS Integer UnderflowEPSS 0.9%CVE-2025-6563MEDIUMCross-site scripting via dst parameter in RouterOS WiFi hotspotEPSS 0.7%