CVE-2026-1439Network attack vector

Script execution via unencoded URL path reflection

Published Feb 18, 2026 · Updated Feb 18, 2026

Reflected XSS in Graylog Web Interface 2.2.3 allows remote attackers to execute JavaScript through a crafted /alerts/ URL. The /alerts/ response inserts attacker-controlled URL path segments into HTML without sanitization or context-appropriate output encoding. No Graylog account is required, but a victim must open the crafted URL; script execution is confined to that browser session and enables limited session-context manipulation.

CVSS severity5.3
Medium
EPSS probability0.18%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reflected XSS in Graylog Web Interface 2.2.3 allows remote attackers to execute JavaScript through a crafted /alerts/ URL. The /alerts/ response inserts attacker-controlled URL path segments into HTML without sanitization or context-appropriate output encoding. No Graylog account is required, but a victim must open the crafted URL; script execution is confined to that browser session and enables limited session-context manipulation.

The record

CVE
CVE-2026-1439
Published
Feb 18, 2026
Updated
Feb 18, 2026
Vendor
Graylog
Product
Graylog Web Interface
Classifications
CWE-79, T1189
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 18, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 18, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=2.2.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Graylog · Graylog Web Interfaceversion=2.2.3

Published CVSS scores

6.1National Institute of Standards and TechnologyCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
5.3Spanish National Cybersecurity Institute, S.A. (INCIBE)CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1189Drive-by Compromise

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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