Keycloak-services: keycloak-services: smtp starttls plaintext credential and message downgrade
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.
CVE-2026-107121
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-2026-107121
Red Hat Build of Keycloak
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
Red Hat Build of Keycloak
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Red Hat Single Sign-On 7
Source reference: /containers/cna/affected/2/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.
[
{
"cpes": [
"cpe:/a:redhat:build_keycloak:"
],
"vendor": "Red Hat",
"product": "Red Hat Build of Keycloak",
"packageName": "keycloak-services",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/a:redhat:build_keycloak:"
],
"vendor": "Red Hat",
"product": "Red Hat Build of Keycloak",
"packageName": "rhbk/keycloak-rhel9",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/a:redhat:red_hat_single_sign_on:7"
],
"vendor": "Red Hat",
"product": "Red Hat Single Sign-On 7",
"packageName": "keycloak-services",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "unaffected"
}
]- Related CVEs
- CVE-2026-107121
Source reference:
/cveMetadata/cveId
Publisher severity
medium
Source reference: /containers/cna/metrics
- Event
- #12023 · Revision 1
- Added to Heist Feed
- Publisher date