GHSA-389x-839f-4rhx is a medium-severity (CVSS 5.5) Uncontrolled Resource Consumption vulnerability in io.netty:netty-common. A fix is available for io.netty:netty-common — see the affected versions and patch details below.
Denial of Service attack on windows app using Netty
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for GHSA-389x-839f-4rhx.
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-389x-839f-4rhx 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 379,842 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
io.netty:netty-commonReal-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
Summary
An unsafe reading of environment file could potentially cause a denial of service in Netty. When loaded on an Windows application, Netty attemps to load a file that does not exist. If an attacker creates such a large file, the Netty application crash.
Details
A similar issue was previously reported in https://github.com/netty/netty/security/advisories/GHSA-xq3w-v528-46rv This issue was fixed, but the fix was incomplete in that null-bytes were not counted against the input limit.
PoC
The PoC is the same as for https://github.com/netty/netty/security/advisories/GHSA-xq3w-v528-46rv with the detail that the file should only contain null-bytes; 0x00.
When the null-bytes are encountered by the InputStreamReader, it will issue replacement characters in its charset decoding, which will fill up the line-buffer in the BufferedReader.readLine(), because the replacement character is not a line-break character.
Impact
Impact is the same as https://github.com/netty/netty/security/advisories/GHSA-xq3w-v528-46rv
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | io.netty:netty-common | all versions | 4.1.118.Finalio.netty:netty-common:4.1.118.Final |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for io.netty:netty-common, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update io.netty:netty-common to 4.1.118.Final or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-389x-839f-4rhx is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-389x-839f-4rhx can be triaged on real exposure rather than presence alone.
Tailored to GHSA-389x-839f-4rhx. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
This issue only affects Windows environments, therefore, this would affect an environment when running a supported Red Hat JBoss EAP 7 or 8, for example, if running on Windows.
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat JBoss Enterprise Application Platform | io.netty/netty-common:4.1.124.Final-redhat-00001 | RHSA-2025:3467 |
| Red Hat JBoss Enterprise Application Platform 7.4.22 | io.netty/netty-common:4.1.119.Final-redhat-00004 | RHSA-2025:4552 |
| Red Hat JBoss Enterprise Application Platform 7.4 for RHEL 8 | eap7-netty-0:4.1.119-1.Final_redhat_00004.1.el8eap | RHSA-2025:3465 |
| Red Hat JBoss Enterprise Application Platform 7.4 for RHEL 8 | eap7-apache-commons-io-0:2.16.1-1.redhat_00001.1.el8eap | RHSA-2025:4549 |
| Red Hat JBoss Enterprise Application Platform 7.4 for RHEL 9 | eap7-apache-commons-io-0:2.16.1-1.redhat_00001.1.el9eap | RHSA-2025:4550 |
| Red Hat JBoss Enterprise Application Platform 7.4 on RHEL 7 | eap7-apache-commons-io-0:2.16.1-1.redhat_00001.1.el7eap | RHSA-2025:4548 |
| Red Hat JBoss Enterprise Application Platform 8 | netty-common | RHSA-2025:3358 |
| Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 8 | eap8-eap-product-conf-parent-0:800.6.1-1.GA_redhat_00001.1.el8eap | RHSA-2025:3357 |
Frequently Asked Questions
Is GHSA-389x-839f-4rhx in your dependencies?
O3 Security finds GHSA-389x-839f-4rhx across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.