CVE-2026-85582 (GCVE-0-2026-85582)
Vulnerability from cvelistv5 – Published: 2026-09-04 11:29 – Updated: 2026-09-04 18:10
VLAI
EPSS
VEX
Title
SiYuan before v3.8.2 Unbounded Session Creation via Basic Auth
Summary
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.
Severity
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-04 18:10 UTC
CWE
- CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/siyuan-note/siyuan/security/ad… | vendor-advisory |
| https://www.vulncheck.com/advisories/siyuan-befor… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| siyuan-note | siyuan |
Affected:
0 , < 3.8.2
(semver)
Unaffected: 3.8.2 (semver) cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:* |
Date Public
2026-08-21 00:00
{
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-85582",
"options": [
{
"Exploitation": "poc"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-09-04T18:10:04.539490Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-09-04T18:10:34.416Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"references": [
{
"tags": [
"exploit"
],
"url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-f4vj-ppp2-5hg4"
}
],
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"packageURL": "pkg:golang/github.com/siyuan-note/siyuan",
"product": "siyuan",
"vendor": "siyuan-note",
"versions": [
{
"lessThan": "3.8.2",
"status": "affected",
"version": "0",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "3.8.2",
"versionType": "semver"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:*",
"versionEndExcluding": "3.8.2",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"credits": [
{
"lang": "en",
"type": "reporter",
"value": "alham-rizvi"
}
],
"datePublic": "2026-08-21T00:00:00.000Z",
"descriptions": [
{
"lang": "en",
"value": "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."
}
],
"metrics": [
{
"cvssV4_0": {
"attackComplexity": "LOW",
"attackRequirements": "NONE",
"attackVector": "NETWORK",
"baseScore": 7.1,
"baseSeverity": "HIGH",
"privilegesRequired": "LOW",
"subAvailabilityImpact": "NONE",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"userInteraction": "NONE",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
"version": "4.0",
"vulnAvailabilityImpact": "HIGH",
"vulnConfidentialityImpact": "NONE",
"vulnIntegrityImpact": "NONE"
},
"format": "CVSS"
},
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 6.5,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"version": "3.1"
},
"format": "CVSS"
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-770",
"description": "Allocation of Resources Without Limits or Throttling",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-09-04T11:29:50.806Z",
"orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
"shortName": "VulnCheck"
},
"references": [
{
"name": "GitHub Security Advisory (GHSA-f4vj-ppp2-5hg4)",
"tags": [
"vendor-advisory"
],
"url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-f4vj-ppp2-5hg4"
},
{
"name": "VulnCheck Advisory: SiYuan before v3.8.2 Unbounded Session Creation via Basic Auth",
"tags": [
"third-party-advisory"
],
"url": "https://www.vulncheck.com/advisories/siyuan-before-3.8.2-unbounded-session-creation-via-basic-auth"
}
],
"title": "SiYuan before v3.8.2 Unbounded Session Creation via Basic Auth",
"x_generator": {
"engine": "vulncheck-endgame"
}
}
},
"cveMetadata": {
"assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
"assignerShortName": "VulnCheck",
"cveId": "CVE-2026-85582",
"datePublished": "2026-09-04T11:29:50.806Z",
"dateReserved": "2026-09-04T10:56:22.465Z",
"dateUpdated": "2026-09-04T18:10:34.416Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2026-85582",
"date": "2026-09-09",
"epss": "0.00371",
"percentile": "0.30377"
},
"nvd": "{\"cve\":{\"id\":\"CVE-2026-85582\",\"sourceIdentifier\":\"disclosure@vulncheck.com\",\"published\":\"2026-09-04T12:17:20.190\",\"lastModified\":\"2026-09-08T20:05:53.177\",\"vulnStatus\":\"Deferred\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"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.\"}],\"affected\":[{\"source\":\"disclosure@vulncheck.com\",\"affectedData\":[{\"vendor\":\"siyuan-note\",\"product\":\"siyuan\",\"defaultStatus\":\"unaffected\",\"packageURL\":\"pkg:golang/github.com/siyuan-note/siyuan\",\"versions\":[{\"version\":\"0\",\"lessThan\":\"3.8.2\",\"versionType\":\"semver\",\"status\":\"affected\"},{\"version\":\"3.8.2\",\"versionType\":\"semver\",\"status\":\"unaffected\"}]}]}],\"metrics\":{\"cvssMetricV40\":[{\"source\":\"disclosure@vulncheck.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"4.0\",\"vectorString\":\"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X\",\"baseScore\":7.1,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"attackRequirements\":\"NONE\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"vulnConfidentialityImpact\":\"NONE\",\"vulnIntegrityImpact\":\"NONE\",\"vulnAvailabilityImpact\":\"HIGH\",\"subConfidentialityImpact\":\"NONE\",\"subIntegrityImpact\":\"NONE\",\"subAvailabilityImpact\":\"NONE\",\"exploitMaturity\":\"NOT_DEFINED\",\"confidentialityRequirement\":\"NOT_DEFINED\",\"integrityRequirement\":\"NOT_DEFINED\",\"availabilityRequirement\":\"NOT_DEFINED\",\"modifiedAttackVector\":\"NOT_DEFINED\",\"modifiedAttackComplexity\":\"NOT_DEFINED\",\"modifiedAttackRequirements\":\"NOT_DEFINED\",\"modifiedPrivilegesRequired\":\"NOT_DEFINED\",\"modifiedUserInteraction\":\"NOT_DEFINED\",\"modifiedVulnConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedVulnIntegrityImpact\":\"NOT_DEFINED\",\"modifiedVulnAvailabilityImpact\":\"NOT_DEFINED\",\"modifiedSubConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedSubIntegrityImpact\":\"NOT_DEFINED\",\"modifiedSubAvailabilityImpact\":\"NOT_DEFINED\",\"Safety\":\"NOT_DEFINED\",\"Automatable\":\"NOT_DEFINED\",\"Recovery\":\"NOT_DEFINED\",\"valueDensity\":\"NOT_DEFINED\",\"vulnerabilityResponseEffort\":\"NOT_DEFINED\",\"providerUrgency\":\"NOT_DEFINED\"}}],\"cvssMetricV31\":[{\"source\":\"disclosure@vulncheck.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H\",\"baseScore\":6.5,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":2.8,\"impactScore\":3.6}],\"ssvcV203\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"ssvcData\":{\"timestamp\":\"2026-09-04T18:10:04.539490Z\",\"id\":\"CVE-2026-85582\",\"options\":[{\"exploitation\":\"poc\"},{\"automatable\":\"no\"},{\"technicalImpact\":\"partial\"}],\"role\":\"CISA Coordinator\",\"version\":\"2.0.3\"}}]},\"weaknesses\":[{\"source\":\"disclosure@vulncheck.com\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-770\"}]}],\"references\":[{\"url\":\"https://github.com/siyuan-note/siyuan/security/advisories/GHSA-f4vj-ppp2-5hg4\",\"source\":\"disclosure@vulncheck.com\"},{\"url\":\"https://www.vulncheck.com/advisories/siyuan-before-3.8.2-unbounded-session-creation-via-basic-auth\",\"source\":\"disclosure@vulncheck.com\"},{\"url\":\"https://github.com/siyuan-note/siyuan/security/advisories/GHSA-f4vj-ppp2-5hg4\",\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\"}]}}",
"vulnrichment": {
"containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-85582\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"poc\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-09-04T18:10:04.539490Z\"}}}], \"references\": [{\"url\": \"https://github.com/siyuan-note/siyuan/security/advisories/GHSA-f4vj-ppp2-5hg4\", \"tags\": [\"exploit\"]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-09-04T18:10:21.656Z\"}}], \"cna\": {\"title\": \"SiYuan before v3.8.2 Unbounded Session Creation via Basic Auth\", \"credits\": [{\"lang\": \"en\", \"type\": \"reporter\", \"value\": \"alham-rizvi\"}], \"metrics\": [{\"format\": \"CVSS\", \"cvssV4_0\": {\"version\": \"4.0\", \"baseScore\": 7.1, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"HIGH\", \"vectorString\": \"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"attackRequirements\": \"NONE\", \"privilegesRequired\": \"LOW\", \"subIntegrityImpact\": \"NONE\", \"vulnIntegrityImpact\": \"NONE\", \"subAvailabilityImpact\": \"NONE\", \"vulnAvailabilityImpact\": \"HIGH\", \"subConfidentialityImpact\": \"NONE\", \"vulnConfidentialityImpact\": \"NONE\"}}, {\"format\": \"CVSS\", \"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 6.5, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"MEDIUM\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H\", \"integrityImpact\": \"NONE\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"HIGH\", \"privilegesRequired\": \"LOW\", \"confidentialityImpact\": \"NONE\"}}], \"affected\": [{\"vendor\": \"siyuan-note\", \"product\": \"siyuan\", \"versions\": [{\"status\": \"affected\", \"version\": \"0\", \"lessThan\": \"3.8.2\", \"versionType\": \"semver\"}, {\"status\": \"unaffected\", \"version\": \"3.8.2\", \"versionType\": \"semver\"}], \"packageURL\": \"pkg:golang/github.com/siyuan-note/siyuan\", \"defaultStatus\": \"unaffected\"}], \"datePublic\": \"2026-08-21T00:00:00.000Z\", \"references\": [{\"url\": \"https://github.com/siyuan-note/siyuan/security/advisories/GHSA-f4vj-ppp2-5hg4\", \"name\": \"GitHub Security Advisory (GHSA-f4vj-ppp2-5hg4)\", \"tags\": [\"vendor-advisory\"]}, {\"url\": \"https://www.vulncheck.com/advisories/siyuan-before-3.8.2-unbounded-session-creation-via-basic-auth\", \"name\": \"VulnCheck Advisory: SiYuan before v3.8.2 Unbounded Session Creation via Basic Auth\", \"tags\": [\"third-party-advisory\"]}], \"x_generator\": {\"engine\": \"vulncheck-endgame\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"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.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-770\", \"description\": \"Allocation of Resources Without Limits or Throttling\"}]}], \"cpeApplicability\": [{\"nodes\": [{\"negate\": false, \"cpeMatch\": [{\"criteria\": \"cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"3.8.2\"}], \"operator\": \"OR\"}]}], \"providerMetadata\": {\"orgId\": \"83251b91-4cc7-4094-a5c7-464a1b83ea10\", \"shortName\": \"VulnCheck\", \"dateUpdated\": \"2026-09-04T11:29:50.806Z\"}}}",
"cveMetadata": "{\"cveId\": \"CVE-2026-85582\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-09-04T18:10:34.416Z\", \"dateReserved\": \"2026-09-04T10:56:22.465Z\", \"assignerOrgId\": \"83251b91-4cc7-4094-a5c7-464a1b83ea10\", \"datePublished\": \"2026-09-04T11:29:50.806Z\", \"assignerShortName\": \"VulnCheck\"}",
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
Loading…
Loading…
Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Loading…
The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Loading…
Loading…