CVE-2026-126625Progressive Robot Ltd hMailServer incorrect default permissions
CVE-2026-126625 is a incorrect default permissions in Progressive Robot Ltd hMailServer, rated medium (6.7 on CVSS 3.1).
Why this priority: Medium severity, with no exploitation signal.
Published · Updated · NVD status: Received
What it is
Files or resources are created with permissions that let others read or change them.
How it is reached
An attacker can exploit it by someone who can already run code or sign in on the machine, with an ordinary user account, but someone has to act first, such as opening a file or following a link. Success also depends on conditions the attacker does not fully control.
What an attacker gains
A successful attack can read the data it protects, change data or behaviour and take it offline. In practice, this kind of flaw lets an attacker use a weak default the deployment never changed.
Is it being exploited?
There is no public report of exploitation yet.
What to do
- No fixed version is listed yet. Find every place Progressive Robot Ltd hMailServer runs, watch the references for a fix, and plan a replacement if it is no longer supported.
- Limit who can run code or sign in on the hosts that run it.
- Warn the people who use it, and filter files and links on the way in.
Description from NVD
Incorrect default permissions in the Windows installer of Progressive Robot hMailServer 6.3.7 allow a local authenticated user to run code as the administrator who installs the product, when it is installed into a new program folder in a location whose permissions let every user write, such as the root of a drive. 6.3.7 fixed CVE-2026-107571 by giving the program folder, Bin and ControlPanel permissions that only administrators may change, but its setup lets Inno Setup make a new program folder first, with the permissions the folder above hands down, and replaces them only afterwards, tens of milliseconds later (33 to 139 milliseconds in the project's test runs). In that time any local account may make files and folders in the new folder, which keep that account as their owner, among them the Bin folder that setup then copies the programs into. Setup runs programs from Bin with the administrator's elevated rights, registering the service among them, before its hardening at the end of setup takes such a folder back, and those programs load a library placed in Bin in place of the system's. The default installation under Program Files, whose folders give ordinary users read and execute only, is not affected.
What this means for your architecture.
A CVE names a product. Whether it matters depends on where that product sits in your systems: what reaches it, which trust boundary it guards and what it can reach once compromised. Veriom maps your components, their relationships and your trust boundaries from your code, cloud and delivery evidence, so you can see where a component like this sits. The radar itself does not look at your systems.
Components it touches
- Default settings, permissions and deployment configuration. The flaw sits between the shipped defaults and a hardened deployment.
Trust boundaries in play
- Host boundary. The attacker needs a foothold on the machine first; the flaw turns a small foothold into a bigger one.
- People who open files and links. Mail, chat and browsers are the delivery path.
- Between the shipped defaults and a hardened deployment. An attacker who crosses it can use a weak default the deployment never changed.
Questions to answer about your own systems
- Where does Progressive Robot Ltd hMailServer run in your systems, and at which version?
- Which of those hosts also run code or users you do not fully trust?
- What can it reach once compromised: which data stores, secrets and services?
Sources
- CVE records and CVSS scores from the NVD CVE API. This product uses the NVD API but is not endorsed or certified by the NVD.
- Exploitation status from CISA’s Known Exploited Vulnerabilities catalog.
- Exploit likelihood from FIRST’s Exploit Prediction Scoring System (EPSS), refreshed daily.
- Explanations are written by Veriom from fixed templates over each record’s data, not by a person reviewing each CVE. Descriptions are quoted from the records as published.