Vulnerability · Published Sep 3, 2026 · Assigned by VulnCheck

CVE-2026-85175SiYuan before v3.8.2 TLS Private Key Disclosure via getFile

High 8.8

In plain English

A high-severity security flaw in siyuan from siyuan-note. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 26% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)8.8High

Exploit odds (30 days)0.3%top 74.3% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

SiYuan versions <= 3.8.1 (fixed in v3.8.2) contain an incomplete blocklist in the IsForbiddenAbsPath() function (kernel/util/path_guard.go), which only blocks conf/conf.json by exact match and does not restrict the TLS private key (conf/key.pem) or CA private key (conf/ca.key) stored in the same conf/ directory. Because the getFile handler skips the blocklist for RoleAdministrator and all authenticated users receive RoleAdministrator in v3.8.1, any user (or any client on a default no-auth-code instance) can retrieve these private keys via POST /api/file/getFile. On deployments with TLS enabled, this allows decryption of captured HTTPS traffic (key.pem) and forging of certificates trusted by clients that imported SiYuan's CA (ca.key).

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Go	github.com/siyuan-note/siyuan/kernel	0.0.0-20260819144130-256d73aa7f94	GHSA-4wwp-f6gw-6qm5
Go	github.com/siyuan-note/siyuan/kernel	0.0.0-20260819144130-256d73aa7f94	GO-2026-6663

Affected products (as reported)

Vendor	Product	Versions
siyuan-note	siyuan	0 – before 3.8.2

Weakness: CWE-552 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

References

GitHub Security Advisory (GHSA-4wwp-f6gw-6qm5) vendor-advisory
VulnCheck Advisory: SiYuan before v3.8.2 TLS Private Key Disclosure via getFile third-party-advisory