CVE Catalog

CVE-2026-123492

MediumCVSS 4.9
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.27%

19th percentile - higher than 19% of all known CVEs

Summary

SiYuan before 3.8.9 contains a nil pointer dereference vulnerability in privateCacheMiddleware that allows authenticated attackers to crash the kernel by reading nonexistent MCP resources. Attackers with a valid API token can send a resources/read request in an initialized MCP session, causing a panic that terminates the kernel process and interrupts service.

Risk Assessment

The organization may experience service disruption of SiYuan due to kernel crash, leading to system unavailability for users.

Recommendation

Update SiYuan to version 3.8.9 or later. Restrict API access and monitor for malformed MCP requests.

Other vulnerabilities in SiYuan

See all
Original NVD description (English source)

SiYuan before 3.8.9 contains a nil pointer dereference vulnerability in privateCacheMiddleware that allows authenticated attackers to crash the kernel by reading nonexistent MCP resources. Attackers with a valid API token can send a resources/read request in an initialized MCP session, causing a panic that terminates the kernel process and interrupts service.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS