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TI-2017-11638 Aliases CVE-2017-15891GHSA-9x4q-j758-h4gx

Improper access control in Synology Calendar

Priority LOW 31CWE-284Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
None · High · None
Fix status
Fixed

Attack profile from CVSS 3.0 · NVD. Fix status from CNA. Impact type from CWE-284.

Summary

Improper access control vulnerability in SYNO.Cal.EventBase in Synology Calendar before 2.0.1-0242 allows remote authenticated users to modify calendar event via unspecified vectors.

Why it matters now

EPSS 0.01036 64th percentileScored 2026-11-07
Fix Fixed Synology Calendar (Synology): 2.0.1-0242

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
SynologySynology Calendarbefore 2.0.1-02422.0.1-0242Patch availableCNA
  • Synology Calendar VendorSynology Affected before 2.0.1-0242 Fixed in 2.0.1-0242 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:synology:calendar:*:*:*:*:*:*:*:*before 2.0.1-0242VulnerableSynology
  • cpe:2.3:a:synology:calendar:*:*:*:*:*:*:*:* Versions before 2.0.1-0242 Vulnerable ·Synology

Remediation

  • Fix · CNA Synology Calendar (Synology) Fixed in 2.0.1-0242

Timeline

  1. 2026-10-02 Threatist record created from CVE-2017-15891
  2. 2026-10-03 Alias added: GHSA-9x4q-j758-h4gx

References

Advisory 1

  • TI-2019-08865 OS command injection in Synology Calendar CVSS 3.1CRITICAL 9.8
  • TI-2022-06947 Cross-site request forgery in Synology Calendar CVSS 3.1HIGH 8.0
  • TI-2021-13806 Hard-coded credentials in Synology Calendar CVSS 3.1HIGH 7.5
  • TI-2018-09547 Path traversal in Synology Calendar CVSS 3.0MEDIUM 6.5
  • TI-2018-06465 Incorrect authorization in Synology Calendar CVSS 3.0MEDIUM 6.5
  • TI-2022-06943 Cross-site scripting in Synology Calendar CVSS 3.1MEDIUM 6.5
See all 10 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences