CVE-2026-107121

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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-107121
https://bugzilla.redhat.com/show_bug.cgi?id=2547296

Configurations

No configuration.

History

07 Oct 2026, 08:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-07 08:16

Updated : 2026-10-07 17:16

NVD link : CVE-2026-107121

Mitre link : CVE-2026-107121

CVE.ORG link : CVE-2026-107121

JSON object : View

Products Affected

No product.

CWE

CWE-319

Cleartext Transmission of Sensitive Information

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