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
MEDIUMPre-NVD 6.56.5—Trending — 3 sources updated this week
EchelonGraph scoreHIGH confidence
Score 6.5 from GitHub Security Advisory published 2026-10-07. The CNA's CVSS baseline 6.5; sources differ by 0.0.
Triggered by: GitHub Security Advisory CVSS
Sources: cna:redhat, ghsa
6.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
- Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: —CVSS: 6.5Exploit: None knownExposed services: Not assessed
No fix is confirmed yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for the fix.
- CVSS v3
- 6.5
- EG Score
- 6.5MEDIUMhigh confidence
- EG Risk
- 29EG Risk 29/100CISA SSVC
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity65% × 45%Exploitation0% × 40%Automatability0% × 15%CISA SSVC: Track at every mission impact level.Action: No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines, and watch the vendor's advisory for the fix. - EPSS PROB
- —
- EPSS %ILE
- —
- KEV
- Not listed
CISA SSVCTrack at every mission impact level.
No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines, and watch the vendor's advisory for the fix.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table
Published
October 7, 2026
Last Modified
October 7, 2026
Advisory Details (2)
Auto-updated Oct 7, 2026No fix on record yet. Sources: redhat.
redhat
2547296 – (CVE-2026-107121) CVE-2026-107121 keycloak-services: keycloak-services: SMTP STARTTLS plaintext credential and message downgrade
https://bugzilla.redhat.com/show_bug.cgi?id=2547296redhatMentions a patch (unverified)
CVE-2026-107121 - Red Hat Customer Portal
Affected: Red Hat Enterprise Linux 8 or OpenShift Container Platform 4, is affected by this vulnerability and a fix may be released to a
https://access.redhat.com/security/cve/CVE-2026-107121Vendor Advisories for CVE-2026-107121(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 7× in last 7d / 7× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-10-07 17:20 UTCEG score recompute
- 2026-10-07 17:20 UTCGHSA enrichment
- 2026-10-07 14:48 UTCEG score recompute
- 2026-10-07 14:48 UTCGHSA enrichment
- 2026-10-07 08:31 UTCEG score recompute
- 2026-10-07 07:57 UTCEG score recompute
- 2026-10-07 07:56 UTCMITRE cvelistV5first tracked
Related CVEs(same CWE)
Frequently asked(4)
What is CVE-2026-107121?
CVE-2026-107121 is a medium vulnerability published on October 7, 2026. 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…
When was CVE-2026-107121 disclosed?
CVE-2026-107121 was first published on October 7, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
What is the CVSS score of CVE-2026-107121?
CVE-2026-107121 has a CVSS base score of 6.5 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-107121?
No fix for CVE-2026-107121 is confirmed yet. Until one is published, restrict network exposure of the affected system or apply the vendor's mitigation — for example, keep it off the internet or limit it to trusted networks — and watch the vendor's advisory for the fix. The vendor advisories EchelonGraph has for CVE-2026-107121 are linked in the Vendor Advisories panel on this page.
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-107121
Is Your Infrastructure Affected by CVE-2026-107121?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.