Auth bypass in Graylog

CVE-2025-30373

Graylog is a free and open log management platform. Starting with 6.1, HTTP Inputs can be configured to check if a specified header is present and has a specified value to authenticate HTTP-based ingestion. Unfortunately, even though in cases of a missing header or a wrong value the correct HTTP response (401) is returned, the message will be ingested nonetheless. To mitigate the vulnerability, disable http-based inputs and allow only authenticated pull-based inputs. This vulnerability is fixed in 6.1.9.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L.

EPSS exploit prediction

EPSS: 0.003 (23.0th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 23rd percentile — 23.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-30373: held from 0.003 to 0.003.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: +0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-30373?
CVE-2025-30373 is a medium-severity vulnerability in Graylog, classified under Improper Authorization. CVSS score: 6.5/10. Published 2025-04-07.
How severe is CVE-2025-30373?
Medium severity. CVSS v3 base score is 6.5 out of 10.