Improper access control vulnerability in SYNO.Cal.EventBase in Synology Calendar before 2.0.1-0242 allows remote authenticated users to mod…

published 2017-12-08 8y ago modified 2026-06-17 4mo ago also EUVD-2017-7310

cvss: 6.5; version 3.0, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 1.0%; EPSS 1.0% chance of exploitation in 30 days, percentile 64%
public exploits: 0; none known

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.

Patch / fix

fixed in 1

synology calendar 2.0.1-0242

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Exploit prediction

1.04% chance of exploitation in the next 30 days, higher than 64% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
NVD	3.0	6.5	CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
NVD	2.0	4.0	AV:N/AC:L/Au:S/C:N/I:P/A:N

Affected products

Synology Synology Calendar

Classification

Weakness

CWE-284 Improper Access Control

References

synology.com /en-global/support/security/Synology_SA_17_68_Calendar
vendor-advisory

Sources

CVE List CVE-2017-15891
NVD CVE-2017-15891

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