CVE-2026-27656
Essential information
- Published
- 25/03/2026 17:16
- Modified
- 26/03/2026 18:51
- Author
- —
- Creator
- —
- CVSS
- 5.7 MEDIUM (v3.1)
- CISA KEV
- No
- CWE
- —
- CVSS vector
-
—
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:H/A:N—
CVSS metrics
- Access vector
- —
- Access complexity
- —
- Authentication
- —
- Confidentiality impact
- —
- Integrity impact
- —
- Availability impact
- —
- Exploitability
- —
- Remediation level
- —
- Report confidence
- —
- Temporal score
- —
- Attack vector
- NETWORK
- Attack complexity
- HIGH
- Privileges required
- HIGH
- User interaction
- REQUIRED
- Scope
- UNCHANGED
- Confidentiality impact
- HIGH
- Integrity impact
- HIGH
- Availability impact
- NONE
- Exploit code maturity
- —
- Remediation level
- —
- Report confidence
- —
- Temporal score
- —
- Attack vector
- —
- Attack complexity
- —
- Attack requirements
- —
- Privileges required
- —
- User interaction
- —
- Confidentiality (V)
- —
- Confidentiality (S)
- —
- Integrity (V)
- —
- Integrity (S)
- —
- Availability (V)
- —
- Availability (S)
- —
- Exploit maturity
- —
Description
Mattermost versions 11.4.x <= 11.4.0, 11.3.x <= 11.3.1, 11.2.x <= 11.2.3, 10.11.x <= 10.11.11 fail to properly validate user identity in the OpenID {{IsSameUser()}} comparison logic, which allows an attacker to take over arbitrary user accounts via an overly permissive substring matching flaw in the user discovery flow.. Mattermost Advisory ID: MMSA-2026-00590
NVD status
- Status
- Analyzed — CVE has been recently published to the CVE List and has been received by the NVD.
- Source
- [email protected]
- NVD
- View on NVD
Affected products (CPE)
| Product | CPE |
|---|---|
| mattermost / mattermost server | cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* |
| mattermost / mattermost server | cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* |
| mattermost / mattermost server | cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* |
| mattermost / mattermost server | cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* |