Outgoing OAuth connection client secret exposure during connection validation
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 require re-entry of the stored client secret when validating an outgoing OAuth connection, which allows an authenticated user with permission to manage outgoing OAuth connections to obtain the secret via pointing the token URL at an attacker-controlled endpoint and triggering validation.. Mattermost Advisory ID: MMSA-2026-00761
CVE-2026-19541
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-19541
Mattermost
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"vendor": "Mattermost",
"product": "Mattermost",
"versions": [
{
"status": "affected",
"version": "11.9.0",
"versionType": "semver",
"lessThanOrEqual": "11.9.1"
},
{
"status": "affected",
"version": "11.8.0",
"versionType": "semver",
"lessThanOrEqual": "11.8.5"
},
{
"status": "affected",
"version": "11.7.0",
"versionType": "semver",
"lessThanOrEqual": "11.7.10"
},
{
"status": "affected",
"version": "11.10.0",
"versionType": "semver",
"lessThanOrEqual": "11.10.1"
},
{
"status": "unaffected",
"version": "11.11.0"
},
{
"status": "unaffected",
"version": "11.9.2"
},
{
"status": "unaffected",
"version": "11.8.6"
},
{
"status": "unaffected",
"version": "11.7.11"
},
{
"status": "unaffected",
"version": "11.10.2"
}
],
"defaultStatus": "unaffected"
}
]- Related CVEs
- CVE-2026-19541
Source reference:
/cveMetadata/cveId
Publisher severity
medium
Source reference: /containers/cna/metrics
- Event
- #32410 · Revision 1
- Added to Heist Feed
- Publisher date