Description
GFI MailEssentials prior to version 21.8 is vulnerable to a .NET deserialization issue. A remote and authenticated attacker can execute arbitrary code by sending crafted serialized .NET when joining to a Multi-Server setup.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| GFI | MailEssentials | < 21.8 | 21.8 |
References
- https://frycos.github.io/vulns4free/2025/04/28/mailessentials.html technical-description exploit
- https://gfi.ai/products-and-solutions/network-security-solutions/mailessentials/resources/documentation/product-releases vendor-advisory
- https://www.vulncheck.com/advisories/gfi-mailessentials-multinode-insecure-deserialization third-party-advisory