Auth bypass in Graylog
CVE-2026-1436
Improper Access Control (IDOR) in the Graylog API, version 2.2.3, which occurs when modifying the user ID in the URL. An authenticated user can access other user's profiles without proper authorization checks. Exploiting this vulnerability allows valid users of the system to be listed and sensitive third-party information to be accessed, such as names, email addresses, internal identifiers, and last activity. The endpoint 'http://<IP>:12900/users/<my_user>' does not implement object-level authorization validations.
Vulnerability class: IDOR (Insecure Direct Object Reference)
EPSS: 0.002 (11.7th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.
Affected products
- Graylog — versions 2.2.3
- Graylog Web Interface — versions 2.2.3
Weakness classification (CWE)
References
- cve-coordination@incibe.es (Third Party Advisory, patch)
Frequently asked questions
- What is CVE-2026-1436?
- CVE-2026-1436 is a medium-severity vulnerability in Graylog, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 6.5/10. Published 2026-02-18.
- How severe is CVE-2026-1436?
- Medium severity. CVSS v3 base score is 6.5 out of 10.