CVE-2026-24423

SmarterTools SmarterMail < Build 9511 Unauthenticated RCE via ConnectToHub API

9.3 CriticalIn KEVPublic exploit

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.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: None

What an attacker can affect

Confidentiality: High
Integrity: High
Availability: High

Exploit likelihood

88.2%Up 88.1 points since Jan 24, 2026

What each source reports

CVE List Score used 9.3

SmarterTools SmarterMail < Build 9511 Unauthenticated RCE via ConnectToHub API

Record: CVE-2026-24423
CVSS 4.0: 9.3 CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Weakness: CWE-306
Updated: 2026-11-02

EUVDEUVD-2026-4273 9.3

Record: EUVD-2026-4273
CVSS 4.0: 9.3 CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Updated: 2026-11-02

GitHub AdvisoriesGHSA-7jpw-fm5p-f98m 9.3

SmarterTools SmarterMail versions prior to build 9511 contain an unauthenticated remote code...

Record: GHSA-7jpw-fm5p-f98m
CVSS 4.0: 9.3 CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS 3.1: 9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness: CWE-306
Updated: 2026-11-02

CISA KEV No score

SmarterTools SmarterMail Missing Authentication for Critical Function Vulnerability

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.

Record: CVE-2026-24423
Weakness: CWE-306
Updated: 2026-11-02

NVD 9.3

Record: CVE-2026-24423
CVSS 4.0: 9.3 CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS 3.1: 9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness: CWE-306
Updated: 2026-11-02

Affected products

Public exploits

Links only. Every CVE stores no exploit code.

Public exploits
Source	Link	Date
PoC in GitHub	aavamin/CVE-2026-24423	2026-01-29
PoC in GitHub	CyberAlp0/SmarterMail-CVE-2026-24423	2026-09-02
Nuclei	SmarterMail - Remote Code Execution

History

History
Recorded	Changed	Sources
Nov 3, 2026	exploitation, exploits
Nov 2, 2026	first indexed	CVE List, EUVD, GitHub Advisories, CISA KEV, Nuclei, NVD, PoC in GitHub

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2026-24423 is a critical vulnerability (CVSS 9.3) in Smartertools Smartermail, published January 23, 2026. CISA lists it as known to be exploited, since February 5, 2026. EUVD reports exploitation since February 5, 2026. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 88.2%, the 99th percentile. No source names a fixed version.