Skip to content

Graylog Allows Session Takeover via Insufficient HTML Sanitization

High severity GitHub Reviewed Published May 7, 2025 in Graylog2/graylog2-server • Updated May 7, 2025

Package

maven org.graylog2:graylog2-server (Maven)

Affected versions

<= 6.0.13
>= 6.1.0, <= 6.1.9

Patched versions

6.0.14
6.1.10

Description

Impact

It is possible to obtain user session cookies by submitting an HTML form as part of an Event Definition Remediation Step field.
For this attack to succeed, the attacker needs a user account with permissions to create event definitions, while the user must have permissions to view alerts. Additionally, an active Input must be present on the Graylog server that is capable of receiving form data (e.g. a HTTP input, TCP raw or syslog etc).

Patches

Workarounds

None, as long as the relatively rare prerequisites are met.

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

References

@kroepke kroepke published to Graylog2/graylog2-server May 7, 2025
Published to the GitHub Advisory Database May 7, 2025
Reviewed May 7, 2025
Published by the National Vulnerability Database May 7, 2025
Last updated May 7, 2025

Severity

High

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H

EPSS score

Exploit Prediction Scoring System (EPSS)

This score estimates the probability of this vulnerability being exploited within the next 30 days. Data provided by FIRST.
(8th percentile)

Weaknesses

CVE ID

CVE-2025-46827

GHSA ID

GHSA-76vf-mpmx-777j

Source code

Loading Checking history
See something to contribute? Suggest improvements for this vulnerability.