8.8
HIGH CVSS 3.1
CVE-2026-85175
SiYuan before v3.8.2 TLS Private Key Disclosure via getFile
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).

INFO

Published Date :

Sept. 3, 2026, 1:06 p.m.

Last Modified :

Sept. 8, 2026, 8:18 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-85175 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 B3log siyuan
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 HIGH [email protected]
CVSS 3.1 HIGH MITRE-CVE
CVSS 4.0 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 HIGH [email protected]
Solution
Update SiYuan to v3.8.2 or later to fix path traversal vulnerability.
  • Update SiYuan to version 3.8.2 or later.
  • Review access controls for sensitive files.
  • Rotate affected private keys if compromised.
  • Ensure proper TLS configuration.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-85175.

URL Resource
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-4wwp-f6gw-6qm5
https://www.vulncheck.com/advisories/siyuan-before-3.8.2-tls-private-key-disclosure-via-getfile
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-4wwp-f6gw-6qm5
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-85175 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-85175 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-85175 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-85175 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Sep. 03, 2026

    Action Type Old Value New Value
    Added Reference https://github.com/siyuan-note/siyuan/security/advisories/GHSA-4wwp-f6gw-6qm5
    Added SSVC {'id': 'CVE-2026-85175', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-09-03T12:11:40.667503Z'}
  • New CVE Received by [email protected]

    Sep. 03, 2026

    Action Type Old Value New Value
    Added 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).
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-552
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/85xxx/CVE-2026-85175.json">CVE-2026-85175</a>
    Added Reference https://github.com/siyuan-note/siyuan/security/advisories/GHSA-4wwp-f6gw-6qm5
    Added Reference https://www.vulncheck.com/advisories/siyuan-before-3.8.2-tls-private-key-disclosure-via-getfile
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.