Vulnerability · Published Oct 8, 2026 · Assigned by GitLab
CVE-2026-107586Allocation of Resources Without Limits or Throttling in hMailServer
Medium 4.3
In plain English
A medium-severity resource allocation without limits in hMailServer from Progressive Robot Ltd. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 27% of all known vulnerabilities).
Official description
Uncontrolled eviction in the browser session table of the REST API in Progressive Robot hMailServer 6.2.28 through 6.3.5 allows a remote authenticated user to end other users' sessions. The table of browser sessions, shared by every account, the server administrator and support sessions, dropped its least recently used session whenever it was full, whoever it belonged to, and placed no limit on how many sessions one account could hold. A user who repeatedly signs in with their own mailbox password can therefore keep the table full and sign out every webmail and administration session that is idle for more than a short time, for as long as they continue.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Progressive Robot Ltd | hMailServer | 6.2.28 – before 6.3.6 |
Weakness: CWE-770 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L