Graylog Allows Stored Cross-Site Scripting via Files Plugin and API Browser

published 2025-05-07 last yr. modified 2026-09-10 2mo ago

cvss: 7.3; version 3.1, GitHub
cisa kev: Not listed; not in CISA's catalog
epss: —; no score, EPSS covers CVEs only
public exploits: 0; none known

### Impact Two minor vulnerabilities were identified in the Graylog2 enterprise server, which can be combined to carry out a stored cross-site scripting attack. An attacker with the permission `FILES_CREATE` can exploit these vulnerabilities to upload arbitrary Javascript code to the Graylog2 server, which - upon requesting of the file by a user of the API browser - results in the execution of this Javascript code in the context of the Graylog frontend application. This enables the attacker to carry out authenticated API requests with the permissions of the logged-in user, thereby taking over the user session.

### Patches The generic API has been removed in 6.2.0 rendering the attack vector unreachable and additional escaping has been added.

Analysis provided by Fabian Yamaguchi - Whirly Labs (Pty) Ltd

Patch / fix

fixed in 1

maven org.graylog2:graylog2-server 6.2.0

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CVSS scores

assigned by	version	score	vector
GitHub	3.1	7.3	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N

Affected packages

ecosystem	package	affected	fixed in
maven	org.graylog2:graylog2-server	<6.2.0	6.2.0

Classification

Weakness

CWE-79 Improper Neutralization of Input During Web Page Generation

References

Sources

GitHub Advisory GHSA-q9q2-3ppx-mwqf

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