CVE-2026-77086

SiYuan before v3.7.4 Path Traversal via packageName

Published Aug 21, 2026 CVSS 4.0 · 9.4 Critical EPSS 1.0% KEV · Not listed
Description
SiYuan before v3.7.4 fails to validate the packageName parameter in Bazaar install and uninstall endpoints, allowing authenticated administrators to perform path traversal via directory traversal sequences. Attackers with admin access can write arbitrary files to any location via install operations or recursively delete directories via uninstall operations by supplying crafted packageName values.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared B3log
B3log siyuan
CPEs cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:*
Vendors & Products B3log
B3log siyuan
Type Values Removed Values Added
First Time appeared Siyuan
Siyuan siyuan
Vendors & Products Siyuan
Siyuan siyuan
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description SiYuan before v3.7.4 fails to validate the packageName parameter in Bazaar install and uninstall endpoints, allowing authenticated administrators to perform path traversal via directory traversal sequences. Attackers with admin access can write arbitrary files to any location via install operations or recursively delete directories via uninstall operations by supplying crafted packageName values.
Title SiYuan before v3.7.4 Path Traversal via packageName
Weaknesses CWE-22
References
Metrics cvssV3_1

{'score': 9.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H'}

cvssV4_0

{'score': 9.4, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
VulnCheck
Published
Updated
Oct 1, 2026, 3:21 PM
Reserved
Aug 20, 2026, 10:55 AM
Status
Deferred
Published
Aug 21, 2026, 11:17 AM
Modified
Oct 16, 2026, 3:10 PM