Medium · CVSS 6.5CVE-2026-107121

Keycloak-services: keycloak-services: smtp starttls plaintext credential and message downgradeCVE-2026-107121

Answer in brief

CVE-2026-107121 records a Medium severity (CVSS 6.5) vulnerability in Keycloak-services: keycloak-services: smtp starttls plaintext credential and message downgrade. The current sources do not mark it as known exploited. The current feed maps Red Hat/keycloak-services (generic), Red Hat/rhbk/keycloak-rhel9 (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Oct 7, 2026Updated Oct 7, 2026Source checked Oct 7, 2026First seen by HOL Oct 7, 2026Material review Oct 7, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 6.5
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Not reported

Why this deserves its current priority

CVSS is 6.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Red Hat/keycloak-services (generic), Red Hat/rhbk/keycloak-rhel9 (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Red Hat/keycloak-servicesgeneric	*	Not reported
Red Hat/rhbk/keycloak-rhel9generic	*	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Red Hat/keycloak-services, Red Hat/rhbk/keycloak-rhel9.
Review the reported fix. Source-reported workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

Evidence timeline and material changes

Published upstream
Oct 7, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Oct 7, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Oct 7, 2026

Sources and claim methodology

Upstream source 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.

Quoted source text, attributed separately from HOL analysis.