CVE-2026-88266: Synology DiskStation Manager external control of configuration vulnerability

CVE-2026-88266 · Severity: medium · CVSS 4.3 · Published 2026-11-12

Synology DiskStation Manager is network storage software that manages files and shared resources on company servers. A vulnerability in the synomount component allows authenticated users to write specific files on the system, potentially compromising data integrity or enabling privilege escalation attacks.

Technologies: Synology DiskStation Manager (DSM). Vendors: Synology.

Quick answers

Is CVE-2026-88266 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-88266 being exploited in the wild.
How severe is CVE-2026-88266?
Medium severity, with a CVSS score of 4.3, published 12 November 2026.
Which products and versions are affected?
Synology DiskStation Manager (DSM) 7.3.2 before 7.3.2-86009-5, 7.4.1 before 7.4.1-90080-1.
Is there a fix for CVE-2026-88266?
Yes: fixed in DSM 7.3.2-86009-5 or above; DSM 7.4.1-90080-1 or above. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-88266 attacked?
It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-88266?
Check whether you run Synology DiskStation Manager (DSM) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • Fixed in: DSM 7.3.2-86009-5 or above; DSM 7.4.1-90080-1 or above

Technical details

An external control of system or configuration setting vulnerability in synomount allows remote authenticated users to write specific files. The vulnerability requires valid authentication credentials and network access to the DSM interface. An attacker can exploit this to modify configuration files or system settings.

Affected products

  • Synology DiskStation Manager (DSM) 7.3.2 before 7.3.2-86009-5, 7.4.1 before 7.4.1-90080-1

Timeline

  • 2026-11-10: disclosed
  • 2026-11-12: advisory

References

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