CVE-2026-1439: Graylog Web Interface · XSS or 'Cross-site Scripting'
Affects Graylog Web InterfaceSource CVE Database V5
Not known to be exploited · CVSS 5.3 Medium.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 11% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 18 Feb 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| GraylogGraylog Web Interface | Affected
| Fixed in– |
AI-suggested
- Immediately restrict access to the Graylog Web Interface to trusted networks and users to reduce exposure.
- Implement strict input validation and output encoding on all user-controllable inputs, especially URL parameters, to prevent injection of malicious scripts.
- Monitor web server logs for suspicious requests targeting the '/alerts/' endpoint with unusual URL patterns.
- Educate users about the risks of clicking unknown or suspicious links, particularly those purporting to lead to Graylog dashboards.
- Apply any available patches or updates from Graylog addressing this vulnerability as soon as they are released.
- Consider deploying Web Application Firewalls (WAFs) with rules to detect and block reflected XSS attempts targeting Graylog interfaces.
- Conduct regular security assessments and penetration tests focusing on web interface vulnerabilities.
- If upgrading is not immediately possible, implement custom output encoding in reverse proxies or web server configurations to mitigate script injection risks.
Description
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.