CVE-2026-59809EPSS p33.3%

CVE-2026-59809CVE-2026-59809

Description

SiYuan before v3.8.0 interpolates secret placeholders into the destination URL parameter of the http_request MCP tool, allowing attackers to exfiltrate stored secrets. An MCP client can craft a request with an attacker-controlled URL containing secret placeholders to send plaintext secret values to any public host without confirmation.

Scoring

CVSS 4.9 ()
VectorCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N
EPSS0.41% probability of exploitation · percentile 33.3% · 2026-10-05T12:00:23Z
Last modified2026-08-26
Sourced from NVD + FIRST.org EPSS. Curated for EU compliance use cases by Adam Lundqvist, Founder at SQUR.