Description
SiYuan versions before v3.7.4 fail to enforce publish-access checks in the getBlockAttrs and batchGetBlockAttrs endpoints. Attackers can retrieve block attributes including names, aliases, memos, and custom fields from protected documents by sending POST requests with block IDs.
Published: 2026-08-12
Score: 6.9 Medium
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

Impact

SiYuan versions before 3.7.4 do not enforce publish‑access checks in the getBlockAttrs and batchGetBlockAttrs endpoints; attackers can send POST requests with block IDs to an exposed API and retrieve block attributes such as names, aliases, memos, and custom fields from protected documents. This flaw represents a missing authorization weakness (CWE-862) that can expose sensitive user data.

Affected Systems

Siyuan Note application, versions earlier than 3.7.4, deployed by any organization that hosts the service.

Risk and Exploitability

The CVSS score of 6.9 indicates moderate risk, and although the EPSS score is unavailable, the vulnerability can be exploited by sending crafted HTTP POST requests to the vulnerable API endpoints without authentication, making it potentially exploitable in environments where the API is reachable over the network. The vulnerability is not currently listed in CISA KEV.

Generated by OpenCVE AI on August 12, 2026 at 23:00 UTC.

Remediation

No vendor fix or workaround currently provided.

OpenCVE Recommended Actions

  • Upgrade SiYuan to version 3.7.4 or later
  • Block unauthenticated access to the getBlockAttrs and batchGetBlockAttrs endpoints using a firewall or reverse‑proxy
  • Implement network segmentation so that only trusted internal services can reach the API surfaces.

Generated by OpenCVE AI on August 12, 2026 at 23:00 UTC.

Tracking

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Advisories

No advisories yet.

History

Fri, 14 Aug 2026 17:15:00 +0000

Type Values Removed Values Added
First Time appeared B3log
B3log siyuan
CPEs cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:*
Vendors & Products B3log
B3log siyuan

Thu, 13 Aug 2026 10:30:00 +0000

Type Values Removed Values Added
First Time appeared Siyuan
Siyuan siyuan
Vendors & Products Siyuan
Siyuan siyuan

Wed, 12 Aug 2026 21:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Wed, 12 Aug 2026 19:30:00 +0000

Type Values Removed Values Added
Description SiYuan versions before v3.7.4 fail to enforce publish-access checks in the getBlockAttrs and batchGetBlockAttrs endpoints. Attackers can retrieve block attributes including names, aliases, memos, and custom fields from protected documents by sending POST requests with block IDs.
Title SiYuan before v3.7.4 Information Disclosure via getBlockAttrs
Weaknesses CWE-862
References
Metrics cvssV3_1

{'score': 5.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N'}

cvssV4_0

{'score': 6.9, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N'}

Subscriptions

B3log Siyuan
Siyuan Siyuan
cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-08-14T16:52:09.591Z

Reserved: 2026-08-10T15:11:49.794Z

Link: CVE-2026-72803

cve-icon Vulnrichment

Updated: 2026-08-12T20:42:06.472Z

cve-icon NVD

Status : Deferred

Published: 2026-08-12T20:17:52.247

Modified: 2026-08-26T16:56:50.830

Link: CVE-2026-72803

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-13T10:15:07Z

Weaknesses