Is there a public exploit for CVE-2026-107889?

No public exploit for CVE-2026-107889 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-107889?

CVE-2026-107889 scores CVSS 5.5 (v3.1), rated medium. EPSS puts the chance of exploitation in the next 30 days at 0.27%.

5.5 Medium

A flaw was found in the login theme rendering component of Keycloak.

CVE-2026-107889

A flaw was found in the login theme rendering component of Keycloak. The issue occurs because the security filter responsible for cleaning user input can be bypassed, allowing a realm administrator to store malicious scripts in display fields. This could result in unauthorized JavaScript execution in the browsers of users visiting the login page, potentially leading to data exposure or session interference.

Assessment

CVSS: 5.5 (v3.1)
Severity: Medium
EPSS: 0.27% chance of exploitation in the next 30 days
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 9 October 2026
Last updated: 3 November 2026
Assigner: redhat

CVSS vectorCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:N

At the source

EUVD (ENISA)

References

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