CVE-2022-41915 is a medium-severity (CVSS 6.5) CWE-113 vulnerability in io.netty:netty-codec-http. 1 public exploit reference exists, so weaponization risk is real. A fix is available for io.netty:netty-codec-http — see the affected versions and patch details below.
Netty vulnerable to HTTP Response splitting from assigning header value iterator
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-2022-41915 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 378,156 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-codec-httpReal-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
When calling DefaultHttpHeaders.set with an iterator of values (as opposed to a single given value), header value validation was not performed, allowing malicious header values in the iterator to perform HTTP Response Splitting.
Patches
The necessary validation was added in Netty 4.1.86.Final.
Workarounds
Integrators can work around the issue by changing the DefaultHttpHeaders.set(CharSequence, Iterator<?>) call, into a remove() call, and call add() in a loop over the iterator of values.
References
HTTP Response Splitting CWE-113: Improper Neutralization of CRLF Sequences in HTTP Headers
For more information
If you have any questions or comments about this advisory:
- Open an issue in [example link to repo](https://github.com/netty/netty)
- Email us at [email protected]
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | io.netty:netty-codec-http | ≥ 4.1.83.Final&&< 4.1.86.Final | 4.1.86.Finalio.netty:netty-codec-http:4.1.86.Final |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
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-codec-http, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update io.netty:netty-codec-http to 4.1.86.Final or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2022-41915 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-2022-41915 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2022-41915. 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.
Frequently Asked Questions
Is CVE-2022-41915 in your dependencies?
O3 Security finds CVE-2022-41915 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.