CVE-2026-86060 PUBLISHED

SSH session privilege manipulation via a crafted username in Mikrotik RouterOS

Assigner: CERT-PL
Reserved: 04.09.2026 Published: 05.09.2026 Updated: 05.09.2026

RouterOS contains an argument-handling flaw in the SSH login path involving usernames that begin with a prohibited character, allowing for the trusted RouterOS policy mask to be changed, leading to privilege escalation. Exploitation requires an unauthenticated SSH session to reach the RouterOS login helper.This issue was fixed in versions: 6.49.21 (Long-term), 7.23.4 (Long-term) and 7.24.2 (Stable)

Metrics

CVSS 4.0

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CVSS Score: 9.2

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	High	Confidentiality	None
Attack Complexity	Low	Integrity	High	Integrity	None
Attack Requirements	Present	Availability	High	Availability	None
Privileges Required	None
User Interaction	None

CVSS 4.0

Product Status

Vendor	Mikrotik
Product	RouterOS
Versions	Default: unaffected affected from 7.24 to 7.24.2 (excl.) affected from 7.0.0 to 7.23.4 (excl.) affected from 6.0.0 to 6.49.21 (excl.)

Credits

Sławomir Rozbicki (CERT.PL) finder

References

Problem Types

CWE-88 Improper neutralization of argument delimiters in a command ('argument injection') CWE