CVE-2026-40536 Synology CVE debrief

Who should care

Defenders responsible for Synology DiskStation Manager (DSM) systems should assess exposure and prioritize patching or mitigation to prevent potential information disclosure. This includes reviewing DSM versions, applying patches or mitigations, and restricting access to sensitive information. Security teams should also monitor for potential information disclosure and review compensating controls for exposed systems.

Why it matters

CVE-2026-40536 is a path traversal vulnerability in Synology DiskStation Manager (DSM) that allows remote authenticated users to obtain non-sensitive information. Defenders responsible for DSM systems should assess exposure and prioritize patching or mitigation to prevent potential information disclosure.

• Potential information disclosure
• Need to verify exposure and apply patches or mitigations
• Possible restriction of access to sensitive information

Technical summary

The vulnerability is caused by an improper limitation of a pathname to a restricted directory ('path traversal') in the Audio API of Synology DiskStation Manager (DSM). This allows remote authenticated users to obtain non-sensitive information. The vulnerability affects DSM versions before 7.2.1-69057-10, 7.2.2-72806-7, and 7.3.2-86009-2. Defenders should prioritize verifying exposure and applying patches or mitigations to prevent potential information disclosure. Synology has provided security advisories that should be reviewed for further details.

Defensive priority

Defenders should prioritize verifying exposure and applying patches or mitigations.

Recommended defensive actions

• Verify exposure by checking DSM versions and applying patches or mitigations
• Monitor for potential information disclosure
• Restrict access to sensitive information
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The CVE record and NVD entry provide limited information about the vulnerability. Further investigation is required to determine the full scope of affected systems and potential impacts. The vulnerability is caused by an improper limitation of a pathname to a restricted directory ('path traversal') in the Audio API of Synology DiskStation Manager (DSM). This allows remote authenticated users to obtain non-sensitive information. Defenders should verify exposure by checking DSM versions and apply patches or mitigations.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.