Auth bypass in Smartertools Smartermail
CVE-2026-24423
SmarterTools SmarterMail versions prior to build 9511 contain an unauthenticated remote code execution vulnerability in the ConnectToHub API method. The attacker could point the SmarterMail to the malicious HTTP server, which serves the ma…
Vulnerability class: Broken Authentication
EPSS: 0.877 (99.7th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Smartertools Smartermail — versions 0
Weakness classification (CWE)
CISA KEV (Known Exploited Vulnerabilities)
This CVE is on the CISA KEV catalog, added on . CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.
BOD 22-01 due date: .
Required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Known ransomware campaign use: yes.
References
- disclosure@vulncheck.com (release-notes, Release Notes, patch)
- disclosure@vulncheck.com (Third Party Advisory, third-party-advisory)
- disclosure@vulncheck.com (Third Party Advisory, third-party-advisory)
- 134c704f-9b21-4f2e-91b3-4a467353bcc0 (US Government Resource)
Frequently asked questions
- What is CVE-2026-24423?
- CVE-2026-24423 is a critical-severity vulnerability in Smartertools Smartermail, classified under Missing Authentication for Critical Function. CVSS score: 9.8/10. Published 2026-01-23.
- How severe is CVE-2026-24423?
- Critical severity. CVSS v3 base score is 9.8 out of 10.
- Is CVE-2026-24423 known to be exploited?
- Yes. CVE-2026-24423 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2026-02-05), indicating it is being actively exploited.