CVE-2026-104658

The Linux live-update apply helper (hmailserver-update) of Progressive Robot hMailServer 6.3.4 and 6.3.5 runs as root on a request file written by the unprivileged hmailserver service account, and took from that request the program used to verify an AppImage update's signature and the systemd unit to stop before reading the service account's files. An attacker who already runs code as the hmailserver service account, for example through another flaw in the mail server, can therefore have arbitrary code executed as root, on any Linux installation where the live update's path unit is active - the default for the project's .deb and .rpm packages - and on AppImage installations run under that unit.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://gitlab.com/hmailserver/hmailserver/-/releases/v6.3.6
https://gitlab.com/hmailserver/hmailserver/-/work_items/58

Configurations

No configuration.

History

08 Oct 2026, 11:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-08 11:16

Updated : 2026-10-08 21:02

NVD link : CVE-2026-104658

Mitre link : CVE-2026-104658

CVE.ORG link : CVE-2026-104658

JSON object : View

Products Affected

No product.

CWE

CWE-807

Reliance on Untrusted Inputs in a Security Decision

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