CVE-2026-107121
Keycloak-services: keycloak-services: smtp starttls plaintext credential and message downgrade
- State
- Published
- Severity
- 6.5 Medium
- Published
- Oct 7, 2026
- Updated
- Oct 7, 2026
- Reserved
- Oct 7, 2026
Description
A flaw was found in the SMTP email configuration handling of the keycloak-services component. When the STARTTLS option is enabled, Keycloak fails to strictly enforce an encrypted connection, allowing it to fall back to unencrypted communication if the encryption request is tampered with. An attacker who can intercept network traffic can exploit this to capture sensitive email credentials and message content in plain text.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 6.5 Medium | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N | redhat |
Weaknesses
- CWE-319 Cleartext Transmission of Sensitive Information
Affected Products
| Product | Versions |
|---|---|
Red Hat Build of KeycloakRed Hat | |
Red Hat Build of KeycloakRed Hat | |
Red Hat Single Sign-On 7Red Hat |
References
- https://access.redhat.com/security/cve/CVE-2026-107121vdb-entry
- RHBZ#2547296issue-tracking
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