CVE-2026-19600
Full vulnerability record from the local CVENow database.
Description
Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10, 11.10.x <= 11.10.1 fail to sanitize authentication tokens before writing them to server log entries, which allows an attacker with access to server logs to obtain valid session tokens or OAuth access tokens and impersonate authenticated users via the debug-level Mattermost server log.. Mattermost Advisory ID: MMSA-2026-00763
Severity
MEDIUM
CVSS score
4.9
(v3.1)
Vulnerability status
Analyzed
Source identifier
Published
2026-10-16 08:17:13.283000
Last modified
2026-10-27 20:58:56.067000
View original CVE JSON
{
"id": "CVE-2026-19600",
"sourceIdentifier": "[email protected]",
"published": "2026-10-16T08:17:13.283",
"lastModified": "2026-10-27T20:58:56.067",
"vulnStatus": "Analyzed",
"cveTags": [],
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"value": "Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10, 11.10.x <= 11.10.1 fail to sanitize authentication tokens before writing them to server log entries, which allows an attacker with access to server logs to obtain valid session tokens or OAuth access tokens and impersonate authenticated users via the debug-level Mattermost server log.. Mattermost Advisory ID: MMSA-2026-00763"
}
],
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{
"source": "[email protected]",
"affectedData": [
{
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"product": "Mattermost",
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},
{
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{
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{
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"metrics": {
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"source": "[email protected]",
"type": "Secondary",
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"userInteraction": "REQUIRED",
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"availabilityImpact": "NONE"
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"type": "Primary",
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"integrityImpact": "NONE",
"availabilityImpact": "NONE"
},
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"id": "CVE-2026-19600",
"options": [
{
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},
{
"automatable": "no"
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{
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],
"role": "CISA Coordinator",
"version": "2.0.3"
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},
"weaknesses": [
{
"source": "[email protected]",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-532"
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"configurations": [
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"source": "[email protected]",
"tags": [
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}