Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1336 CNY

100%
Buy Us a Coffee

CVE-2026-85584— SiYuan before v3.8.2 Denial of Service via Auth Throttle

Quick assessment

Affected
siyuan-note siyuan
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

SiYuan 在 v3.8.2 之前版本中，发布服务的 Basic Auth 限流机制存在拒绝服务（DoS）漏洞。该机制使用由攻击者控制的、未经验证的用户名来存储认证失败的尝试状态，且未强制执行容量限制或数据淘汰策略。未经身份验证的攻击者可以通过提交带有唯一且无效的用户名的一系列认证请求，从而耗尽内存并增加同步开销，进而降低服务的可用性。

CVSS 7.5 · High

Possible ATT&CK Techniques 1 AI

T1499 · Endpoint Denial of Service

Affected Version Matrix 2

VendorProduct Version RangeStatus
siyuan-note siyuan < 3.8.2 affected
3.8.2 unaffected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-85584

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
SiYuan before v3.8.2 Denial of Service via Auth Throttle
Source: CVE Program / CVE List V5
Vulnerability Description
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.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
不加限制或调节的资源分配
Source: CVE Program / CVE List V5

Affected Products

Vendor Product Affected Versions CPE Subscribe
siyuan-note siyuan 0 ~ 3.8.2 -

II. Public POCs for CVE-2026-85584

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-85584

请登录查看更多情报信息。

Vendor Advisories for CVE-2026-85584 (2)

Same Patch Batch · siyuan-note · 2026-09-04 · 8 CVEs total

CVE-2026-85581 7.5 HIGH SiYuan before v3.8.2 Denial of Service via unauthenticated UI-process registration
CVE-2026-85585 7.5 HIGH SiYuan before v3.8.2 Unbounded Memory Consumption via ControlConcurrency
CVE-2026-85578 6.5 MEDIUM SiYuan through 3.8.1 Authorization Bypass via getFile
CVE-2026-85583 6.5 MEDIUM SiYuan before v3.8.2 Path Traversal via symlink in file API
CVE-2026-85582 6.5 MEDIUM SiYuan before v3.8.2 Unbounded Session Creation via Basic Auth
CVE-2026-85580 6.5 MEDIUM SiYuan before v3.8.2 Path Guard Bypass via Case Mismatch
CVE-2026-85579 4.3 MEDIUM SiYuan before v3.8.2 Information Disclosure via undoState

IV. Related Vulnerabilities

Same product: siyuan
Same vendor: siyuan-note
Same weakness: CWE-770

V. Comments for CVE-2026-85584

No comments yet

Leave a comment