---
id: CVE-2026-85584
title: >-
  SiYuan versions before v3.8.2 contain a denial of service vulnerability in the
  publish-service Basic Auth throttle that stores failed-attempt state using
  attacker-controlled usernames without enforcing capacity limits or eviction
  policie…
summary: >-
  SiYuan versions before v3.8.2 contain a denial of service vulnerability in the
  publish-service Basic Auth throttle that stores failed-attempt state using
  attacker-controlled usernames without enforcing capacity limits or eviction
  policie…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-770
vendor: siyuan-note
product: siyuan
affected:
  - siyuan < 3.8.2
published: '2026-09-04'
updated: '2026-09-08'
sourceUpdated: '2026-09-08T20:05:53.177'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-85584'
references:
  - url: >-
      https://github.com/siyuan-note/siyuan/security/advisories/GHSA-2x7j-p79w-7744
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/siyuan-before-3.8.2-denial-of-service-via-auth-throttle
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/siyuan-note/siyuan/security/advisories/GHSA-2x7j-p79w-7744
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
  - cve.org
  - exploit-available
epss: 0.00328
epssPercentile: 0.26052
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-08T14:43:22.966505Z'
ingestedAt: '2026-09-08T15:33:26.960Z'
---

## Overview

SiYuan versions before v3.8.2 contain a denial of service vulnerability in the publish-service Basic Auth throttle that stores failed-attempt state using attacker-controlled usernames without enforcing capacity limits or eviction policies. Unauthenticated attackers can submit repeated authentication requests with unique invalid usernames to exhaust memory and increase synchronization overhead, degrading service availability.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.