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.
- Vendor
- SmarterTools
- Product
- SmarterMail
- CVSS
- 9.8
- EPSS (exploit probability)
- 88.2%
- Status
- kevransomware use
- CISA patch-by (BOD 22-01)
- Added to KEV
Is CVE-2026-24423 being exploited?
Yes. CISA added CVE-2026-24423 to its Known Exploited Vulnerabilities catalog on . CISA only lists a CVE when it has reliable evidence of exploitation in the wild. CISA marks it as known to be used in ransomware campaigns.
FIRST's EPSS model puts the probability of exploitation activity in the next 30 days at 88.2% (scored October 14, 2026).
- CISA KEV[ LISTED ]
- ENISA EUVD (exploited)[ — ]
- CIRCL KEV[ — ]
Catalog snapshot 2026-10-21. Full cross-catalog view: /kev-comparison
What to do
CISA required actionApply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
US federal civilian agencies must remediate by (21 days after listing) under BOD 22-01. Everyone else: that deadline is a sensible upper bound, not a target. Vendor guidance and the NVD record are linked under Source above.
Other SmarterTools SmarterMail CVEs we track
| CVE / Vulnerability | Severity | CVSS | EPSS | Added to KEV |
|---|---|---|---|---|
| CVE-2026-23760 SmarterTools SmarterMail Authentication Bypass Using an Alternate Path or Channel Vulnerabilityransomware use | [ CRITICAL ] | 9.8 | 96.4% | |
| CVE-2025-52691 SmarterTools SmarterMail Unrestricted Upload of File with Dangerous Type Vulnerabilityransomware use | [ CRITICAL ] | 10.0 | 85.7% |