Keycloak (netty-codec-http): Schwachstelle ermöglicht Manipulation von Dateien
WID-SEC-2026-0212 · first 26.01.2026 · updated 16.10.2026 · CVSS 6,5
What it is about
Keycloak ermöglicht Single Sign-On mit Identity and Access Management für moderne Anwendungen und Dienste. Ein entfernter, anonymer Angreifer kann eine Schwachstelle in Keycloak ausnutzen, um Dateien zu manipulieren.
Under what conditions?
Over the network and without logging in. This is the most dangerous combination: attackers can scan reachable devices automatically.
What can happen in the worst case
An attacker could use the vulnerability to
- Dateien zu manipulieren
Am I affected?
Affected according to the BSI:
- Debian Linux
- IBM License Metric Tool
- IBM DB2
- IBM SAN Volume Controller
- IBM Storwize
- IBM FlashSystem
- Open Source Keycloak <26.5.2
- IBM SPSS Analytic Server
- Dell Secure Connect Gateway <5.36.00.16
The installed version is usually shown under “Help → About” or in the device’s admin interface.
What helps?
Update to at least:
- Open Source Keycloak 26.5.2
- Dell Secure Connect Gateway 5.36.00.16
Is the vulnerability already being exploited?
None of the CVEs is in the CISA catalogue of exploited vulnerabilities. That does not mean there are no attacks, only that none are documented.
Information and sources
- Original BSI advisory (WID)
- Keycloak Release Notes vom 2026-01-25 www.keycloak.org
- NIST Vulnerability Database vom 2026-01-25 nvd.nist.gov
- Debian Security Advisory DSA-6160 vom 2026-03-12 security-tracker.debian.org
- Debian Security Advisory DLA-4519 vom 2026-03-31 lists.debian.org
- IBM Security Bulletin 7269426 vom 2026-04-15 www.ibm.com
- IBM Security Bulletin 7273312 vom 2026-05-18 www.ibm.com
- IBM Security Bulletin 7274848 vom 2026-06-02 www.ibm.com
- IBM Security Bulletin 7280219 vom 2026-07-21 www.ibm.com
- Dell Security Advisory DSA-2026-386 vom 2026-09-01 www.dell.com
- IBM Security Bulletin 7292669 vom 2026-10-15 www.ibm.com
CVE: CVE-2025-67735
Source: BSI warning and information service (CERT-Bund); CISA. The assessment of the conditions is my reading of the BSI text; the external pages are in their original language.