CVE-2025-9076
Full vulnerability record from the local CVENow database.
Description
Mattermost versions 10.10.x <= 10.10.1 fail to properly sanitize user data during shared channel membership synchronization, which allows malicious or compromised remote clusters to access sensitive user information via unsanitized user objects. This vulnerability affects Mattermost Server instances with shared channels enabled.
Severity
MEDIUM
CVSS score
6.5
(v3.1)
Vulnerability status
Analyzed
Source identifier
Published
2025-09-15 10:15:32.450000
Last modified
2026-10-19 17:10:00.173000
View original CVE JSON
{
"id": "CVE-2025-9076",
"sourceIdentifier": "[email protected]",
"published": "2025-09-15T10:15:32.450",
"lastModified": "2026-10-19T17:10:00.173",
"vulnStatus": "Analyzed",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "Mattermost versions 10.10.x <= 10.10.1 fail to properly sanitize user data during shared channel membership synchronization, which allows malicious or compromised remote clusters to access sensitive user information via unsanitized user objects. This vulnerability affects Mattermost Server instances with shared channels enabled."
},
{
"lang": "es",
"value": "Mattermost versiones 10.10.x menor o igual que 10.10.1 no logran sanear correctamente los datos de usuario durante la sincronización de membresía de canales compartidos, lo que permite a clústeres remotos maliciosos o comprometidos acceder a información sensible del usuario a través de objetos de usuario no saneados. Esta vulnerabilidad afecta a instancias del servidor Mattermost con canales compartidos habilitados."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "Mattermost",
"product": "Mattermost",
"defaultStatus": "unaffected",
"versions": [
{
"version": "10.10.0",
"lessThanOrEqual": "10.10.1",
"versionType": "semver",
"status": "affected"
},
{
"version": "10.11.0",
"status": "unaffected"
},
{
"version": "10.10.2",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
"source": "[email protected]",
"type": "Secondary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N",
"baseScore": 6.5,
"baseSeverity": "MEDIUM",
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"privilegesRequired": "HIGH",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"availabilityImpact": "NONE"
},
"exploitabilityScore": 1.2,
"impactScore": 5.2
},
{
"source": "[email protected]",
"type": "Primary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
"baseScore": 6.5,
"baseSeverity": "MEDIUM",
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "NONE",
"availabilityImpact": "NONE"
},
"exploitabilityScore": 2.8,
"impactScore": 3.6
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2025-09-15T14:05:07.348669Z",
"id": "CVE-2025-9076",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "total"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"weaknesses": [
{
"source": "[email protected]",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-862"
}
]
}
],
"configurations": [
{
"nodes": [
{
"operator": "OR",
"negate": false,
"cpeMatch": [
{
"vulnerable": true,
"criteria": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
"versionStartIncluding": "10.10.0",
"versionEndExcluding": "10.10.2",
"matchCriteriaId": "F3861BBC-7E0F-4782-9666-4EF12C1ABDF5"
}
]
}
]
}
],
"references": [
{
"url": "https://mattermost.com/security-updates",
"source": "[email protected]",
"tags": [
"Vendor Advisory"
]
}
]
}