CVE-2026-107578 (GCVE-0-2026-107578)

Vulnerability from cvelistv5 – Published: 2026-10-08 11:47 – Updated: 2026-10-08 14:17
VLAI
Title
Improper Link Resolution Before File Access ('Link Following') in hMailServer
Summary
Improper link resolution and external control of file paths in the administrative command-line operations of hMailServer.exe in Progressive Robot hMailServer 6.3.4 and 6.3.5 allow a local attacker who already runs code as the low-privilege service account to escalate privilege. On Windows, operations run with administrator rights by the installer, DBSetup, the Control Panel or an administrator wrote log entries and crash records into the log folder, created, deleted and changed the permissions of the self-signed certificate and private key in the data folder, and rewrote message files in the data folder, all by path in folders the service account (NT SERVICE\hMailServer, the default for new installations since 6.3.4) can modify, following junctions and mount points; and the store-maintenance operations reached files by names taken from the database, which the service account can write, including names outside the data folder. On Linux, the store-maintenance and object-storage operations run as root followed symbolic links the service account (the packaged hmailserver user, which owns the data folder) planted in it, so a root-run operation read, wrote or removed the link's target as root. A local attacker controlling the service account can thereby gain the administrator's (Windows) or root's (Linux) privileges when such an operation is run.
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-08 14:17 UTC
CWE
  • CWE-59 - Improper Link Resolution Before File Access ('Link Following')
Assigner
GitLab CNA under the mitre root
CNA scorecard C 75/100 over 288 records in the last 180 days details
Impacted products
Vendor Product Version CPE status
Progressive Robot Ltd hMailServer Affected: 6.3.4 , < 6.3.6 (semver)
guessed Create a notification for this product.
Show details on NVD website

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