CVE-2026-107121: medium-severity vulnerability in Red Hat Build of Keycloak
Keycloak-services: keycloak-services: smtp starttls plaintext credential and message downgrade
Published
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.5epss 0.1%
exploitation probability
0.1%top 100% of all CVEs
observed exploitation
nono source reports it
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:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N
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