CVE-2025-25193 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 CVE-2025-25193.
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
CVE-2025-25193 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 378,567 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 CVE-2025-25193 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 CVE-2025-25193 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2025-25193. 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 CVE-2025-25193 in your dependencies?
O3 Security finds CVE-2025-25193 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.