CVEs / CVE-2026-24423
CVE-2026-24423: SmarterTools SmarterMail Missing Authentication for Critical Function Vulnerability
- Known exploited in the CISA KEV catalog since 5 Feb 2026
- critical 9.8 CVSS 3.1 (NVD)
- EPSS 88.1% chance of exploitation in the next 30 days, higher than 99% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
SmarterTools SmarterMail contains a missing authentication for critical function vulnerability in the ConnectToHub API method. This could allow the attacker to point the SmarterMail instance to a malicious HTTP server which serves the malicious OS command and could lead to command execution.
Description
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 malicious OS command. This command will be executed by the vulnerable application.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| SmarterTools SmarterMail | before 100.0.9511 | 100.0.9511 |
Exploitation
| In CISA KEV since | 5 Feb 2026 |
|---|---|
| Due date for US federal agencies | 26 Feb 2026 |
| Used in ransomware campaigns | Known |
| 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. |
Severity
| CVSS 3.1 | 9.8 criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HScored by NVD |
|---|---|
| Weakness | CWE-306 |
References
- CVE-2026-24423 on NVD
- CVE-2026-24423 in the CISA KEV catalog
- https://www.smartertools.com/smartermail/release-notes/current (cited by CISA)
- https://www.cve.org/CVERecord?id=CVE-2026-24423 (cited by CISA)
- https://code-white.com/public-vulnerability-list/#systemadminsettingscontrollerconnecttohub-missing-authentication-in-smartermail Third Party Advisory
- https://www.smartertools.com/smartermail/release-notes/current Release Notes
- https://www.vulncheck.com/advisories/smartertools-smartermail-unauthenticated-rce-via-connecttohub-api Third Party Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-24423 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.