HAProxyMessageDecoder Stack Exhaustion DoS

Exploitation

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

CVSS

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

EPSS

• CVE-2022-41881: 1.58% estimated exploitation activity in the next 30 days; percentile 75.50 (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 A StackOverflowError can be raised when parsing a malformed crafted message due to an infinite recursion. Patches Users should upgrade to 4.1.86.Final. Workarounds There is no workaround, except using a custom HaProxyMessageDecoder. References When parsing a TLV with type = PP2TYPESSL, the value can be again a TLV with type = PP2TYPESSL and so on. The only limitation of the recursion is that the TLV length cannot be bigger than 0xffff because it is encoded in an unsigned short type. Providing a TLV with a nesting level that is large enough will lead to raising of a StackOverflowError. The StackOverflowError will be caught if HAProxyMessageDecoder is used as part of Netty’s ChannelPipeline, but using it directly without the ChannelPipeline will lead to a thrown exception / crash. For more information If you have any questions or comments about this advisory: Open an issue in netty

Published by the source

12 Dec 2022, 21:24 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-fx2c-96vj-985v

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# Patch Next advisory brief: CVE-2022-41881

Advisory: HAProxyMessageDecoder Stack Exhaustion DoS
IDs: CVE-2022-41881, GHSA-fx2c-96vj-985v
Record: https://patchnext.com/advisories/cve-2022-41881 (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 5.3)
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-haproxy 4.1.86.Final. A vendor fix does not mean a deployment is fixed.

## Affected components
- Maven io.netty:netty-codec-haproxy: affected < 4.1.86.Final; fixed in 4.1.86.Final

## Suggested inspection (read-only)
- Maven io.netty:netty-codec-haproxy: 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-haproxy.
- 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-fx2c-96vj-985v (GitHub-reviewed advisory GHSA-fx2c-96vj-985v lists affected ranges: Maven io.netty:netty-codec-haproxy >=0 <4.1.86.Final)

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