GHSA-3xf8-g8gr-g7rh is a medium-severity (CVSS 5.7) CWE-384 vulnerability in org.graylog2:graylog2-server. A fix is available for org.graylog2:graylog2-server — see the affected versions and patch details below.
Graylog session fixation vulnerability through cookie injection
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-3xf8-g8gr-g7rh.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-3xf8-g8gr-g7rh plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,166 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
org.graylog2:graylog2-server☕org.graylog2:graylog2-serverReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
Impact
Reauthenticating with an existing session cookie would re-use that session id, even if for different user credentials. In this case, the pre-existing session could be used to gain elevated access to an existing Graylog login session, provided the malicious user could successfully inject their session cookie into someone else's browser.
The complexity of such an attack is high, because it requires presenting a spoofed login screen and injection of a session cookie into an existing browser, potentially through an XSS attack. No such attack has been discovered.
Patches
Graylog 5.1.11 and 5.2.4, and any versions of the 6.0 development branch contain patches to not re-use sessions under any circumstances, making this type of attack impossible.
Workarounds
Using short session expiration and explicit log outs of unused sessions can help limiting the attack vector. Unpatched this vulnerability exists, but is relatively hard to exploit.
A proxy could be leveraged to clear the authentication cookie for the Graylog server URL for the /api/system/sessions endpoint, as that is the only one vulnerable.
Analysis provided by Fabian Yamaguchi - Whirly Labs (Pty) Ltd
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.graylog2:graylog2-server | ≥ 4.3.0&&< 5.1.11 | 5.1.11org.graylog2:graylog2-server:5.1.11 |
| ☕Maven | org.graylog2:graylog2-server | ≥ 5.2.0-alpha.1&&< 5.2.4 | 5.2.4org.graylog2:graylog2-server:5.2.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.graylog2:graylog2-server, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.graylog2:graylog2-server to 5.1.11 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-3xf8-g8gr-g7rh is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-3xf8-g8gr-g7rh can be triaged on real exposure rather than presence alone.
Tailored to GHSA-3xf8-g8gr-g7rh. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-3xf8-g8gr-g7rh in your dependencies?
O3 Security finds GHSA-3xf8-g8gr-g7rh across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.