CVE-2026-67276 — Mikrotik RouterOS

What is CVE-2026-67276?

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)

The record classifies CVE-2026-67276 under weakness class CWE-347. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 58 days ago.

Severity and exploitation probability

CVSS v4.0 base score: 9.2 — Critical (derived from score)
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
EPSS (FIRST): 0.2% probability of exploitation in the next 30 days, higher than 16.1% of all scored CVEs
CISA KEV: Not listed in the CISA Known Exploited Vulnerabilities catalog
Threadlinqs priority: 7.2/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
Published: 2026-09-05

Is CVE-2026-67276 being exploited?

Weaponised exploit code for CVE-2026-67276 is publicly available. 2 public proof-of-concept repositories are tracked for this identifier. It currently carries a trending score of 42 in the Threadlinqs vulnerability feed.

dinosn/mikrotrick-poc (github)
trickest/cve (trickest)

Affected products and versions

Mikrotik: RouterOS

How to fix CVE-2026-67276

No vendor patch reference has been recorded for CVE-2026-67276 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

Threat activity tracking CVE-2026-67276

3 tracked threats in the Threadlinqs corpus reference CVE-2026-67276, either in the campaign’s CVE list or as an indicator on the campaign record.

CISA Adds Two Actively Exploited KEVs: SharePoint Code Injection (CVE-2026-65660) and Mikrotik RouterOS Auth Bypass (CVE-2026-67279) — CRITICAL · 2026-09-26
CISA Adds Actively Exploited WSO2 API Manager and Adobe Commerce Flaws to KEV Catalog, Warns on SharePoint Code Injection — CRITICAL · 2026-09-25
Attackers Hijack MikroTik Routers Through Internet-Exposed SSH Without Authentication (MikroTrick) — CRITICAL · 2026-09-06

Sources

Enriched from CVE.org, NVD, FIRST EPSS, GitHub Security Advisories, public proof-of-concept repositories. Last verified by Threadlinqs on 2026-09-06. This product uses the NVD API but is not endorsed or certified by the NVD.

Vendor advisory and patch