XSS in Graylog
CVE-2026-1439
Reflected Cross-Site Scripting (XSS) vulnerability in the Graylog Web Interface console, version 2.2.3, caused by a lack of proper sanitization and escaping in HTML output. Several endpoints include segments of the URL directly in the response without applying output encoding, allowing an attacker to inject and execute arbitrary JavaScript code when a user visits a specially crafted URL. Exploitation of this vulnerability may allow script execution in the victim's browser and limited manipulation of the affected user's session context, through the '/ alerts /' endpoint.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.002 (7.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 7th percentile — 7.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000
Affected products
- Graylog — versions 2.2.3
- Graylog Web Interface — versions 2.2.3
Weakness classification (CWE)
References
- www.incibe.es/en/incibe-cert/notices/aviso/multiple-vulnerabilities-graylog (Third Party Advisory, patch)
Frequently asked questions
- What is CVE-2026-1439?
- CVE-2026-1439 is a medium-severity vulnerability in Graylog, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-02-18.
- How severe is CVE-2026-1439?
- Medium severity. CVSS v3 base score is 6.1 out of 10.