SSH session privilege manipulation via a crafted username in Mikrotik RouterOS
Affects RouterOS 6.0.0 before 6.49.21, 7.0.0 before 7.23.4, and 7.24 before 7.24.2 when SSH logins are involved. Fixed in 7.24.2, 7.23.4 and 6.49.21.
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Listed in CISA KEV
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Actively exploited
- Fix
- Fixed in 7.24.2, 7.23.4, 6.49.21
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
MikroTik RouterOS, the operating system used on MikroTik routers, is affected by a flaw in its SSH login process where specially crafted usernames can alter the system's security permissions. This could allow an attacker who can reach the SSH service to gain higher privileges than they should have.
Summarized by anthropic/claude-haiku-5.5. Verify details against the original sources.
Read the original description
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)
Timeline
- CVE published
- Added to CISA KEV
CISA has evidence of exploitation in the wild
- Record last updated
- CISA remediation deadline
Due date for US federal agencies to patch
Affected versions
- Mikrotik RouterOS
From 7.24 · fixed in 7.24.2; From 7.0.0 · fixed in 7.23.4; From 6.0.0 · fixed in 6.49.21
References 7
cert.pl
mikrotik.com
Questions about CVE-2026-86060
What does this mean?
A specially crafted username used during SSH login can give the SSH session more rights than the user should have.Source: mikrotik.com
Am I affected, and how do I check?
Affected versions are RouterOS 6.0.0 before 6.49.21, 7.0.0 before 7.23.4, and 7.24 before 7.24.2. Compare the version shown on the device's system information with these ranges to see which branch applies.Source: mikrotik.com
What should I do about it?
Upgrade to 7.24.2 if on the 7.24 branch, 7.23.4 if on 7.x before 7.24, or 6.49.21 if on 6.x.Source: mikrotik.com
Is it being exploited?
Yes. CISA added it to its Known Exploited Vulnerabilities catalog on 2026-09-10, which means it has evidence of attacks. No public exploit code is tracked.Source: cisa.gov, cve.now feed data