TI-2025-07813 Aliases CVE-2025-8533 GHSA-8g5c-fvxq-mw4m

Incorrect Authorization of XPC Service in Fantastical.app

LOW 37CWE-863Published 2025-08-07 · Updated 2025-08-07

Key facts

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

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-863.

Summary

A vulnerability was identified in the XPC services of Fantastical. The services failed to implement proper client authorization checks in its listener:shouldAcceptNewConnection method, unconditionally accepting requests from any local process. As a result, any local, unprivileged process could connect to the XPC service and access its methods. This issue has been resolved in version 4.0.16.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00415 36th percentileScored 2026-11-07

Fix Fixed Fantastical (Flexibits): 4.0.16

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: Yes
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Flexibits	Fantastical	before 4.0.16	4.0.16	Patch available	CNA

Fantastical VendorFlexibits Affected before 4.0.16 Fixed in 4.0.16 Patch available CNA

Remediation

Fix · CNA Fantastical (Flexibits) Fixed in 4.0.16

Timeline

2026-10-02 Threatist record created from CVE-2025-8533
2026-10-03 Alias added: GHSA-8g5c-fvxq-mw4m

References

Advisory 1

https://cert.pl/en/posts/2025/08/CVE-2025-8533

Other 1

https://flexibits.com/fantastical

Sources

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