Graylog through 7.1.4 validates outbound URLs against an allowlist before making requests but fails to re-validate after following HTTP redirects. Attackers with lookup table or event notification permissions can craft allowlisted endpoints that redirect to internal services, enabling the server to fetch and return internal responses.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
None
No data modification
Availability
None
No disruption
CVSS Vector v4.0
Weakness Type (CWE)
Vulnerable Products
graylog2:graylog2-server
References 4
https://github.com/Graylog2/graylog2-server
disclosure@vulncheck.com
https://github.com/Graylog2/graylog2-server/blob/abb14d1/graylog2-server/src/ma…
disclosure@vulncheck.com
https://github.com/Graylog2/graylog2-server/issues/26591
disclosure@vulncheck.com
https://www.vulncheck.com/advisories/graylog-through-7.1.4-server-side-request-…
disclosure@vulncheck.com