Netty vulnerable to HTTP Response splitting from assigning header value iterator

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

6.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

EPSS

• CVE-2022-41915: 0.95% estimated exploitation activity in the next 30 days; percentile 61.37 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

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 Email us at netty-security@googlegroups.com

Published by the source

12 Dec 2022, 21:25 UTC

Last modified by the source

29 Jan 2023, 05:03 UTC

Source last checked

26 Oct 2026, 16:02 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-hh82-3pmq-7frp

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# Patch Next advisory brief: CVE-2022-41915

Advisory: Netty vulnerable to HTTP Response splitting from assigning header value iterator
IDs: CVE-2022-41915, GHSA-hh82-3pmq-7frp
Record: https://patchnext.com/advisories/cve-2022-41915 (revision 1, source checked 26 Oct 2026, 16:02 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: io.netty:netty-codec-http 4.1.86.Final. A vendor fix does not mean a deployment is fixed.

## Affected components
- Maven io.netty:netty-codec-http: affected >= 4.1.83.Final, < 4.1.86.Final; fixed in 4.1.86.Final

## Suggested inspection (read-only)
- Maven io.netty:netty-codec-http: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on io.netty:netty-codec-http.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-hh82-3pmq-7frp (GitHub-reviewed advisory GHSA-hh82-3pmq-7frp lists affected ranges: Maven io.netty:netty-codec-http >=4.1.83.Final <4.1.86.Final)

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