SiYuan v3.7.0 before v3.8.6 contains an absolute path traversal vulnerability in the kernel's private plugin HTTP server, which passes a kernel plugin handler's ResponseFile.Path to gin's Context.File without validation. Attackers supplying a malicious kernel plugin can return an absolute path to read any file readable by the SiYuan process, including the API token and conf.json.
CVE-2026-109309
MEDIUMPre-NVD 6.56.5Trending — 4 sources updated this week
EchelonGraph scoreHIGH confidence
“—” beside the score: it is equal to the CVSS score beside it.
Score 6.5 from GitHub Security Advisory published 2026-10-12. A secondary CVSS source baseline 6.5; sources differ by 0.0.
Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, a secondary CVSS source
6.5EG
EchelonGraph verdictMonitorRemediate within your standard update timelines at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
- Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.4%CVSS: 6.5Exploit: None knownExposed services: Not assessed
A fix is referenced (a reference tagged "Patch", often a source commit), but no release containing it is confirmed — find the release that contains it; until it is applied, mitigate (WAF / firewall / segmentation).
- CVSS v3
- 6.5
- EG Score
- 6.5MEDIUMhigh confidence
- EG Risk
- 44EG Risk 44/100
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computed (value × EchelonGraph’s weight)Severity65% × 45%The EG Score, 6.5 of 10.Exploitation0.4% × 40%FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.Automatability100% × 15%CISA's SSVC Automatable value: yes (Vulnrichment).SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Attend at high (mission-essential systems).Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.Action: A fix is referenced, but no release containing it is confirmed. Check the referenced fix and the vendor's advisory for a release that contains it and apply that within your standard update timelines at low or medium mission impact and sooner than that at high; until then, restrict network exposure of the affected system or apply the vendor's mitigation. - EPSS PROB
- 0.4%
- EPSS %ILE
- 30th
- KEV
- Not listed
SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Attend at high (mission-essential systems).
A fix is referenced, but no release containing it is confirmed. Check the referenced fix and the vendor's advisory for a release that contains it and apply that within your standard update timelines at low or medium mission impact and sooner than that at high; until then, restrict network exposure of the affected system or apply the vendor's mitigation.
Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; 60 days if it is not.
In CISA KEV no (CISA's KEV catalog) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it
Published
October 12, 2026
Last Modified
October 13, 2026
Advisory Details (3)
Auto-updated Oct 13, 2026🔬 Proof of concept available. Fix referenced — no release confirmed yet. Sources: github_commit, github.
Web page
SiYuan v3.7.0 before v3.8.6 Arbitrary File Read via Plugin ResponseFile.Path | Advisories | VulnCheck
https://www.vulncheck.com/advisories/siyuan-3.7.0-before-3.8.6-arbitrary-file-read-via-plugin-responsefile-pathGitHub advisoryMentions a patch (unverified)🟡 PoC Available
Kernel plugin handler returns arbitrary file content via ResponseFile.Path with no path validation · Advisory · siyuan-note/siyuan · GitHub
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-phmw-4rgv-r4xvGitHub commit
commit c6494375ea40 (siyuan-note/siyuan)
Fix landed in siyuan-note/siyuan commit c6494375ea40 — awaiting tagged release
https://github.com/siyuan-note/siyuan/commit/c6494375ea40ee973f430f0e85d50f1862a30d81Vendor Advisories for CVE-2026-109309(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 8× in last 7d / 8× in last 30d)
Each row is a time one of our pipelines fetched, updated or re-scored this CVE. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.
- 2026-10-13 17:31 UTCEG score recompute
- 2026-10-13 17:31 UTCGHSA enrichmentGHSA-g3cr-c99q-2hfc · GitHub CVSS 6.5
- 2026-10-13 17:09 UTCEG score recompute
- 2026-10-13 17:09 UTCGHSA enrichmentGHSA-g3cr-c99q-2hfc · GitHub CVSS 6.5
- 2026-10-13 16:33 UTCEPSS rescoreEPSS 0.4% · 30th percentile
- 2026-10-12 17:27 UTCEG score recompute
- 2026-10-12 16:27 UTCEG score recomputeFirst assessed: 6.5 MEDIUM
- 2026-10-12 16:25 UTCMITRE cvelistV5first tracked
Related CVEs(same CWE)
Frequently asked(5)
What is CVE-2026-109309?
CVE-2026-109309 is a medium-severity vulnerability; its CVE record was published on October 12, 2026. SiYuan v3.7.0 before v3.8.6 contains an absolute path traversal vulnerability in the kernel's private plugin HTTP server, which passes a kernel plugin handler's ResponseFile.Path to gin's Context.File without validation. Attackers supplying a malicious kernel plugin can return an absolute path to…
When was CVE-2026-109309 made public?
CVE-2026-109309 was made public on September 24, 2026: that is the date its CVE record's CNA, VulnCheck, gives for when the vulnerability was made public. The CVE record itself was published on October 12, 2026. EchelonGraph's copy of the record carries a last-modified date of October 13, 2026; the record at its source may have been updated since.
Is CVE-2026-109309 actively exploited?
CVE-2026-109309 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.4% probability of exploitation in the next 30 days (30th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-109309?
CVE-2026-109309 has a CVSS base score of 6.5 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-109309?
A fix for CVE-2026-109309 is referenced (a reference tagged "Patch", often a source commit), but EchelonGraph has no release containing it on record. Check that reference and the vendor's advisory for a release that contains the fix and update to it; until then, restrict network exposure of the affected system or apply the vendor's mitigation. The vendor advisories EchelonGraph has for CVE-2026-109309 are linked in the Vendor Advisories panel on this page.
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-109309
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