siyuan-note SiYuan up to 3.8.1 Publish Service Basic Auth denial of service

CVSS Meta Temp Score
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CTI Interest Score
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5.3$0-$5k0.41

Summaryinfo

A vulnerability categorized as problematic has been discovered in siyuan-note SiYuan up to 3.8.1. The affected element is an unknown function of the component Publish Service Basic Auth Handler. Such manipulation leads to denial of service. This vulnerability is documented as CVE-2026-85582. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in siyuan-note SiYuan up to 3.8.1. Affected by this issue is an unknown functionality of the component Publish Service Basic Auth Handler. The manipulation with an unknown input leads to a denial of service vulnerability. Using CWE to declare the problem leads to CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. Impacted is availability. CVE summarizes:

SiYuan versions before v3.8.2 contain an unbounded session creation vulnerability in the publish-service Basic Auth handler that allows authenticated attackers to exhaust memory. Attackers can repeatedly authenticate with valid credentials to create persistent session entries without expiry or capacity limits, causing indefinite process memory growth and denial of service.

The advisory is shared for download at github.com. This vulnerability is handled as CVE-2026-85582 since 09/04/2026. The exploitation is known to be easy. The attack may be launched remotely. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1499.

Upgrading to version 3.8.2 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.5
CNA Vector (VulnCheck): 🔒

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: SiYuan 3.8.2

Timelineinfo

09/04/2026 Advisory disclosed
09/04/2026 +0 days CVE reserved
09/04/2026 +0 days VulDB entry created
09/04/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-85582 (🔒)
GCVE (CVE): GCVE-0-2026-85582
GCVE (VulDB): GCVE-100-398756

Entryinfo

Created: 09/04/2026 13:57
Changes: 09/04/2026 13:57 (76)
Complete: 🔍
Cache ID: 216::103

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