CVE-2026-67276
highpriority · act · 90OT risk · criticalEU KEV · CERT.PLEPSS 0.089 · 95 %ileexploit · PoCDENLRUUSEU KEVflagged by CERT.PLreported 2026-09-05patched 2026-09-03
RouterOS does not compare the complete RSA public key when matching an SSH authentication request to an authorized user key, checking the key type and modulus but omitting the exponent. Because signature verification uses the client-supplied key, an attacker knowing an authorized RSA modulus can supply a key with exponent one, forge a valid signature, and open an SSH command channel as the target user without the private key.This issue was fixed in versions: 6.49.21 (Long-term), 7.23.4 (Long-term) and 7.24.2 (Stable)
EPSS · scored 2026-10-26
RouterOS does not compare the complete RSA public key when matching an SSH authentication request to an authorized user key, checking the key type and modulus but omitting the exponent. Because signature verification uses the client-supplied key, an attacker knowing an authorized RSA modulus can supply a key with exponent one, forge a valid signature, and open an SSH command channel as the target user without the private key.This issue affects only 7.x branch was fixed in versions: 7.23.4 (Long-term) and 7.24.2 (Stable)
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 8.1–9.2
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
exploits (4)
Public proof-of-concept and weaponised exploit code.
- HORKimhab/CVE-2026-67276CVE-2026-67276 - Draft or TODOPoC · poc_in_github
affected products (14)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- NCSC-2026-0345Kwetsbaarheden verholpen in MikroTik RouterOSNL2026-09-08csaf · ncsc_nlNL
MikroTik heeft meerdere kwetsbaarheden verholpen in RouterOS.
- WID-SEC-W-2026-3193MikroTik RouterOS: Mehrere SchwachstellenDeutsch2026-09-06csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in MikroTik RouterOS ausnutzen, um Sicherheitsvorkehrungen zu umgehen, um Informationen offenzulegen, um einen Denial of Service Zustand herbeizuführen und um die Kontrolle über betroffene Geräte zu übernehmen.
also known as (1)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (6) nvd
External citations — patches, advisories, analysis.
- https://cert.pl/en/posts/2026/09/mikrotik-routeros-cveThird Party Advisory
- https://cert.pl/en/posts/2026/09/vulnerabilities-in-mikrotik-routeros-actively-exploited/MitigationThird Party Advisory
- https://forum.mikrotik.com/t/7-23-4-long-term-is-released/272801Release Notes
- https://forum.mikrotik.com/t/7-24-2-stable-is-released/272800Release Notes
- https://mikrotik.com/supportsec/september-2026-vulnerability/Vendor Advisory
- https://npratley.net/reversing-mikrotiks-silent-patch-the-routeros-7-23-4-fix-they-wouldnt-explain/ExploitThird Party Advisory
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